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divya.1024
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Fractions, Decimals and Percentages Guide 2 Page 97, prob 12

by divya.1024 Thu Nov 21, 2013 8:27 pm

Hi there,

I could understand half of the solution for this one. I could not understand the full solution on page 101. It says image reduces by 13%. alright, it is now 87% only. Now again there is another 13% reduction in image. So, how does it work this way? I assumed, it has to be again multiply by 13% * 87 which is 11.31. Can anyone please explain to me! I am so confused!

Thanks & appreciate in advance.
Divya
tommywallach
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Re: Fractions, Decimals and Percentages Guide 2 Page 97, prob 12

by tommywallach Sun Nov 24, 2013 2:09 pm

Hey Divya,

If you want to reduce something, you multiply by (100 - %reduction)/100.

So if you want to reduce something by 13%, you multiply by .87, and if you want to increase something by 13%, you multiply by 1.13.

Make sense?

-t
divya.1024
Course Students
 
Posts: 19
Joined: Wed Aug 07, 2013 10:08 am
 

Re: Fractions, Decimals and Percentages Guide 2 Page 97, prob 12

by divya.1024 Sun Nov 24, 2013 9:36 pm

I had a class today, and this helped me better.. thanks!
tommywallach
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Posts: 1917
Joined: Thu Mar 31, 2011 11:18 am
 

Re: Fractions, Decimals and Percentages Guide 2 Page 97, prob 12

by tommywallach Tue Nov 26, 2013 7:55 pm

Glad to hear it! : )

-t