{"id":18152,"date":"2019-09-30T17:16:10","date_gmt":"2019-09-30T17:16:10","guid":{"rendered":"https:\/\/www.manhattanprep.com\/gmat\/?p=18152"},"modified":"2019-11-22T15:41:20","modified_gmt":"2019-11-22T15:41:20","slug":"how-to-review-a-data-sufficiency-question","status":"publish","type":"post","link":"https:\/\/www.manhattanprep.com\/gmat\/blog\/how-to-review-a-data-sufficiency-question\/","title":{"rendered":"How to Review a Data Sufficiency Question"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-16950\" src=\"https:\/\/www.manhattanprep.com\/gmat\/wp-content\/uploads\/sites\/18\/2019\/02\/should-i-retake-the-gmat.png\" alt=\"Manhattan Prep GMAT Blog - Data Sufficiency\" width=\"1200\" height=\"628\" srcset=\"https:\/\/www.manhattanprep.com\/gmat\/wp-content\/uploads\/sites\/18\/2019\/02\/should-i-retake-the-gmat.png 1200w, https:\/\/www.manhattanprep.com\/gmat\/wp-content\/uploads\/sites\/18\/2019\/02\/should-i-retake-the-gmat-300x157.png 300w, https:\/\/www.manhattanprep.com\/gmat\/wp-content\/uploads\/sites\/18\/2019\/02\/should-i-retake-the-gmat-768x402.png 768w, https:\/\/www.manhattanprep.com\/gmat\/wp-content\/uploads\/sites\/18\/2019\/02\/should-i-retake-the-gmat-1024x536.png 1024w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><\/p>\n<p><span style=\"font-weight: 400;\">You\u2019ve heard it here before: <\/span><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/juice-gmat-quant-problems\/\"><span style=\"font-weight: 400;\">reviewing practice problems is even more valuable than doing them<\/span><\/a><span style=\"font-weight: 400;\">. Here\u2019s a step-by-step guide to reviewing your GMAT Data Sufficiency problems.\u00a0<\/span><\/p>\n<p><!--more--><\/p>\n<h2><b>Which Data Sufficiency questions should I review?<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">If you had infinite time, you\u2019d want to review every Data Sufficiency problem you do. But, let\u2019s be realistic! You have my permission to <\/span><b>not<\/b><span style=\"font-weight: 400;\"> review these types of problems:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Easy problems that you got right with no stress<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Problems with content that you haven\u2019t started studying<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">The very hardest problems (well above your goal score level)<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">One note on that first bullet point: <\/span><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/how-to-review-easy-gmat-quant-questions-and-why-theyre-important\/\"><span style=\"font-weight: 400;\">reviewing easy problems is still worthwhile<\/span><\/a><span style=\"font-weight: 400;\">, and if you have time, you should dive into the easy problems. But, if you\u2019re pressed for time, focus on reviewing these problems:\u00a0<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Problems that are moderate to \u201cmoderately hard\u201d in difficulty<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Problems you got right, but spent too much time solving or didn\u2019t feel confident about<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Problems you got wrong despite having already studied the material\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Any problem that surprised you or taught you a lesson about the GMAT<\/span><\/li>\n<\/ul>\n<p><b>Don\u2019t<\/b><span style=\"font-weight: 400;\"> ever spend a whole study session reviewing one or two super-tough problems. I know it\u2019s infuriating to walk away from a problem without understanding it. But, <\/span><b>walking away from a <\/b><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/high-value-gmat-quant\/\"><b>low-value problem<\/b><\/a><b> is a victory, not a defeat<\/b><span style=\"font-weight: 400;\">. Spend your review time on problems that will teach you practical lessons you can use right now. If you need the material from that 800-level problem in the future, you can always go back and review it then.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Okay, so you have a list of problems to review. What does reviewing a problem actually look like?\u00a0<\/span><\/p>\n<h2><b>Reviewing a Data Sufficiency problem<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">The first step is to redo the problem. However, you\u2019re going to do the problem differently this time. When you redo while reviewing, don\u2019t use a timer. Feel free to use any outside resources you\u2019d like, such as a calculator or the <\/span><a href=\"https:\/\/www.amazon.com\/GMAT-All-Quant-definitive-Manhattan\/dp\/1506248543\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">All the Quant Guide<\/span><\/a><span style=\"font-weight: 400;\">. That\u2019s right &#8212; you\u2019re allowed to \u201ccheat\u201d as much as you want! The only thing you <\/span><b>can\u2019t<\/b><span style=\"font-weight: 400;\"> use is the explanation. I\u2019ll say that again, because it really matters:<\/span><\/p>\n<p style=\"text-align: center;\"><b>DO NOT READ THE EXPLANATION (YET)!<\/b><\/p>\n<p><span style=\"font-weight: 400;\">When you read the explanation too soon, you\u2019re robbing yourself of a chance to solve the problem. And you\u2019ll learn more from solving the problem\u2014even if it\u2019s a struggle and even if you need to cheat!\u2014than you will from watching someone else solve it.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If you get stuck, check the explanation, but <\/span><b>stop reading as soon as it gives you a good clue<\/b><span style=\"font-weight: 400;\">. Then, go back to your own paper and try to finish the work yourself. If you absolutely can\u2019t get anywhere, even with multiple clues from the explanation, the problem might be too hard right now. Save it for later &#8212; and if this happens repeatedly with the same type of problem, that\u2019s a sign that you should review that topic!\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Once you\u2019re satisfied with your own redo of the problem, feel free to read the rest of the explanation. Take note of anything that the explanation did that you didn\u2019t do, or vice versa. Sometimes, the explanation can point you in the direction of a faster or simpler solution.\u00a0<\/span><\/p>\n<h2><b>Learning from a Data Sufficiency problem\u00a0<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">Now, it\u2019s time to take some notes. But you <\/span><b>aren\u2019t<\/b><span style=\"font-weight: 400;\"> just going to write down how to solve the problem. That would help you remember how to solve <\/span><i><span style=\"font-weight: 400;\">this<\/span><\/i><span style=\"font-weight: 400;\"> exact problem, but that\u2019s not the point. Here\u2019s what your goals really are at this stage:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Learn (at least) one thing about the GMAT.<\/span><\/li>\n<li style=\"font-weight: 400;\"><span style=\"font-weight: 400;\">Learn (at least) one thing about yourself.\u00a0<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">Before we keep going, let\u2019s do an actual Data Sufficiency problem, so we\u2019re all on the same page. Here\u2019s one from <\/span><a href=\"https:\/\/www.mba.com\/exams\/gmat\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">mba.com<\/span><\/a><span style=\"font-weight: 400;\">\u2019s GMATPrep:<\/span><\/p>\n<blockquote><p><span style=\"font-weight: 400;\">A bookstore that sells used books sells each of its paperback books for a certain price and each of its hardcover books for a certain price. If Joe, Maria, and Paul bought books in this store, how much did Maria pay for 1 paperback book and 1 hardcover book?<\/span><\/p>\n<p><span style=\"font-weight: 400;\">(1) Joe bought 2 paperback books and 3 hardcover books for $12.50.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">(2) Paul bought 4 paperback books and 6 hardcover books for $25.00.<\/span><\/p><\/blockquote>\n<p><span style=\"font-weight: 400;\">Do the problem now! Next, we\u2019ll walk through which notes you should take in your <\/span><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/error-log-the-1-way-to-raise-your-gmat-score\/\"><span style=\"font-weight: 400;\">problem log<\/span><\/a><span style=\"font-weight: 400;\">.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">A Data Sufficiency problem has two different things you need to analyze while solving: the question stem, and the statements. Take some notes on each.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">First, write down <\/span><b>anything that stands out about the question stem<\/b><span style=\"font-weight: 400;\">, and <\/span><b>what you think you should do when you see those things in a Data Sufficiency question. <\/b><span style=\"font-weight: 400;\">Your exact notes will vary depending on your strengths and weaknesses, how you solved the problem, and why you\u2019re reviewing it. Here are some examples.<\/span><\/p>\n<blockquote>\n<p style=\"text-align: left;\"><b>Student 1 <\/b><span style=\"font-weight: 400;\">spent too long on this problem because she dove into the statements without understanding the problem. She didn\u2019t realize, until too late in the process, that solving with equations would have been much simpler. Here are her notes on the question stem:\u00a0<\/span><\/p>\n<p style=\"text-align: left;\"><i><span style=\"font-weight: 400;\">Word problem = turn into variables BEFORE dealing w\/ statements!<\/span><\/i><\/p>\n<p style=\"text-align: left;\"><b>Student 2<\/b><span style=\"font-weight: 400;\"> read the question stem and assumed she\u2019d need to solve for the price of each book individually, instead of solving for the sum of two prices. Here are her notes:\u00a0<\/span><\/p>\n<p style=\"text-align: left;\"><i><span style=\"font-weight: 400;\">Look for \u201ccombos\u201d where the ? asks for a sum:<\/span><\/i> <i><span style=\"font-weight: 400;\">hardcover AND paperback price = H + P<\/span><\/i><\/p>\n<p style=\"text-align: left;\"><i><span style=\"font-weight: 400;\">Could still solve even without H or P separately<\/span><\/i><\/p>\n<p style=\"text-align: left;\"><i><span style=\"font-weight: 400;\">Write down the exact question, don\u2019t assume!<\/span><\/i><\/p>\n<p style=\"text-align: left;\"><b>Student 3<\/b><span style=\"font-weight: 400;\"> got this one right, but still thought it was an interesting problem! Here are her notes:\u00a0<\/span><\/p>\n<p style=\"text-align: left;\"><i><span style=\"font-weight: 400;\">Q is \u201cwhat is H + P\u201d : look out for tricky statements that tell you the sum, like \u201c2H + 2P = 10\u201d!<\/span><\/i><\/p>\n<\/blockquote>\n<p><span style=\"font-weight: 400;\">Next, go through the statements one at a time. Here\u2019s where things really get interesting. <\/span><b>If you missed the problem<\/b><span style=\"font-weight: 400;\">, then you either thought an insufficient statement was actually sufficient, or thought a sufficient statement was actually insufficient. Figure out where things went wrong first: which statement(s) did you analyze incorrectly? (For a very deep dive into these two types of mistakes, check out our articles on <\/span><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/heres-why-you-might-be-missing-gmat-data-sufficiency-problems-part-1\/\"><span style=\"font-weight: 400;\">type 1 errors<\/span><\/a><span style=\"font-weight: 400;\"> and <\/span><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/heres-why-you-might-be-missing-gmat-data-sufficiency-problems-part-1-2\/\"><span style=\"font-weight: 400;\">type 2 errors<\/span><\/a><span style=\"font-weight: 400;\">.)<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If you thought a statement was <\/span><b>sufficient<\/b><span style=\"font-weight: 400;\"> and you were wrong, <\/span><b>figure out why you thought it was sufficient<\/b><span style=\"font-weight: 400;\">. Then, in your notes, <\/span><b>prove that it was insufficient<\/b><span style=\"font-weight: 400;\">. That will probably involve writing down specific cases, even if you wouldn\u2019t take the time to do that on test day. When you\u2019re reviewing, take all the time you need!<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If you thought a statement was <\/span><b>insufficient<\/b><span style=\"font-weight: 400;\"> and you were wrong, <\/span><b>figure out why you thought it was insufficient. <\/b><span style=\"font-weight: 400;\">Then, <\/span><b>prove that it was sufficient<\/b><span style=\"font-weight: 400;\">. That means demonstrating to yourself, in your notes, exactly how the statement helps you answer the question, and what answer it leads to.\u00a0<\/span><\/p>\n<blockquote><p><b>Student 1<\/b><span style=\"font-weight: 400;\"> got the problem right eventually, but realized when reviewing that she didn\u2019t need to test cases. Here are her notes on the statements:\u00a0<\/span><\/p>\n<p><i><span style=\"font-weight: 400;\">DS word problem: turn into math equations and see if the algebra is easy BEFORE you think about cases&#8230;cases work but take a long time!<\/span><\/i><\/p>\n<p><b>Student 2<\/b><span style=\"font-weight: 400;\"> made the first type of mistake when she put the statements together. She thought the statements were sufficient together, but they actually weren\u2019t. Let\u2019s see her notes:\u00a0<\/span><\/p>\n<p><i><span style=\"font-weight: 400;\">Statements were insufficient together! I thought they were sufficient b\/c there were two equations and two variables in the question.\u00a0<\/span><\/i><\/p>\n<p><i><span style=\"font-weight: 400;\">Proof: statements simplify to the same thing, 2p + 3h = 12.5. If the statements are the same, C CAN\u2019T be the right answer. The answer must be either D or E. Word problem to algebra = check to make sure the statements aren\u2019t identical, don\u2019t assume C if it seems easy!<\/span><\/i><\/p>\n<p><b>Student 3<\/b><span style=\"font-weight: 400;\"> got this one right, but she\u2019s still taking notes so she remembers any tricks this problem tried to play! Here are her notes.\u00a0<\/span><\/p>\n<p><i><span style=\"font-weight: 400;\">DS linear equations: simplify statements to double check that the statements aren\u2019t = to each other. If 2 statements are different, you can solve for two variables. But if they\u2019re the same, you can\u2019t solve at all (unless the statement is the same as the question.)\u00a0<\/span><\/i><\/p><\/blockquote>\n<p><span style=\"font-weight: 400;\">By the way, the answer to the question was (E). I didn\u2019t tell you until now because of exactly what I wrote earlier &#8212; the more you play around with a problem on your own before letting somebody else tell you what to do, the more you\u2019ll remember about it later.<\/span><\/p>\n<h2><b>What do I do with all of these notes?\u00a0<\/b><\/h2>\n<p><span style=\"font-weight: 400;\">From each problem you\u2019ve reviewed, you\u2019ve learned something about the GMAT\u2014and you\u2019ve hopefully learned something about how <\/span><i><span style=\"font-weight: 400;\">you<\/span><\/i><span style=\"font-weight: 400;\"> tend to approach problems and the mistakes you make most often. What do you do with all of this information?\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">GMAT instructor Elaine Loh suggests a method in <\/span><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/error-log-the-1-way-to-raise-your-gmat-score\/\"><span style=\"font-weight: 400;\">this article<\/span><\/a><span style=\"font-weight: 400;\"> that everybody should try out. For each problem you learned something from, set a date about two weeks in the future to redo it again. For instance, you could have a study session once per week where you redo all of the old problems from a couple of weeks ago. Write down these dates in your problem log, and build a habit of checking it regularly and actually redoing the problems you\u2019ve listed. Also, she recommends that when you have a few minutes of spare time, you simply read over the notes you\u2019ve taken in your problem log. No need to do anything fancy &#8212; just quickly reread your takeaways once or twice a week, to jog your memory of the interesting DS problems you\u2019ve reviewed so far.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">If Data Sufficiency is a strong area for you, it\u2019s okay to keep your problem logging low-key. Just jot down a couple of notes on problems you missed (unless they\u2019re way too hard!). But if you want to improve your DS performance, be more aggressive in reviewing DS problems for a couple of weeks, and you may notice a change in how you think about these problems.\u00a0<\/span><\/p>\n<h4>Want some more GMAT review tips? Check out these posts.<\/h4>\n<ul>\n<li><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/how-to-review-a-sentence-correction-question\/\">How to Review a GMAT Sentence Correction Question<\/a><\/li>\n<li><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/how-to-review-a-gmat-critical-reasoning-problem\/\">How to Review a GMAT Critical Reasoning Problem<\/a><\/li>\n<li><a href=\"https:\/\/www.manhattanprep.com\/gmat\/blog\/how-to-review-a-gmat-reading-comprehension-question\/\">How to Review a GMAT Reading Comprehension Question<\/a><\/li>\n<\/ul>\n<p><em><strong>Don\u2019t forget\u00a0that you can attend the first session of any of our online or in-person GMAT courses absolutely free. We\u2019re not kidding! <a href=\"https:\/\/www.manhattanprep.com\/gmat\/classes\/free\/\" target=\"_blank\" rel=\"noopener\">Check out our upcoming courses here<\/a>.<\/strong><\/em><\/p>\n<hr \/>\n<p><b><i><em><strong><a id=\"bloglink\" href=\"https:\/\/www.manhattanprep.com\/instructors\/chelsey-cooley\/\" target=\"_blank\" rel=\"noopener noreferrer\">Chelsey Cooley<\/a><a href=\"https:\/\/www.manhattanprep.com\/instructors\/chelsey-cooley\/?utm_source=manhattanprep.com%2Fgre%2Fblog&#038;utm_medium=blog&#038;utm_content=CooleyBioGREBlog&#038;utm_campaign=GRE%20Blog\" target=\"_blank\" rel=\"noopener noreferrer\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft\" title=\"Chelsey Cooley Manhattan Prep GRE Instructor\" src=\"https:\/\/cdn2.manhattanprep.com\/gre\/wp-content\/uploads\/sites\/19\/2015\/11\/chelsey-cooley-150x150.jpg\" alt=\"Chelsey Cooley Manhattan Prep GRE Instructor\" width=\"150\" height=\"150\" data-pin-nopin=\"true\" \/><\/a>\u00a0is a Manhattan Prep instructor based in Seattle, Washington.<\/strong>\u00a0<\/em><\/i><\/b><i><em>Chelsey always followed her heart when it came to her education. Luckily, her heart led her straight to the perfect background for GMAT and GRE teaching: she has undergraduate degrees in mathematics and history, a master\u2019s degree in linguistics, a 790 on the GMAT, and a perfect 170Q\/170V on the GRE. <a href=\"https:\/\/www.manhattanprep.com\/gmat\/classes\/#instructor\/336\"><span style=\"font-weight: 400;\">Check out Chelsey\u2019s upcoming GMAT prep offerings here<\/span><\/a><span style=\"font-weight: 400;\">.<\/span><\/em><\/i><\/p>\n","protected":false},"excerpt":{"rendered":"<p>You\u2019ve heard it here before: reviewing practice problems is even more valuable than doing them. Here\u2019s a step-by-step guide to reviewing your GMAT Data Sufficiency problems.\u00a0<\/p>\n","protected":false},"author":127,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[929,52871,930,52878],"tags":[53063,233,271,353],"yst_prominent_words":[56087,54184,56085,56092,55705,56091,53704,56093,53787,54561,56089,56096,56424,56095,56097,56090,56086,56098,53786,56094],"class_list":["post-18152","post","type-post","status-publish","format-standard","hentry","category-gmat-prep","category-gmat-strategies","category-gmat-study-guide","category-manhattan-prep","tag-data-sufficiency-questions","tag-gmat","tag-gmat-how-to-study","tag-gmat-study-tips"],"_links":{"self":[{"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/posts\/18152","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/users\/127"}],"replies":[{"embeddable":true,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/comments?post=18152"}],"version-history":[{"count":8,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/posts\/18152\/revisions"}],"predecessor-version":[{"id":18353,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/posts\/18152\/revisions\/18353"}],"wp:attachment":[{"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/media?parent=18152"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/categories?post=18152"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/tags?post=18152"},{"taxonomy":"yst_prominent_words","embeddable":true,"href":"https:\/\/www.manhattanprep.com\/gmat\/wp-json\/wp\/v2\/yst_prominent_words?post=18152"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}