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kpkanupriyakhmi
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RE: FDPs Guide, 1.5a rounding

by kpkanupriyakhmi Sat Feb 28, 2015 8:32 am

Q 9:- didn't understand the explanation
tommywallach
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Re: FDPs Guide, 1.5a rounding

by tommywallach Sun Mar 01, 2015 9:14 pm

Hey KP,

Well, 1/3rd of the jar is red marbles and 1/2 is blue. 1/3 + 1/2 = 5/6. So we know that 5/6 of the jar is either red or blue. That leaves 1/6 of the jar to be...anything else.

The question tells us that there are only 25 marbles remaining, and they're all white. So we now know that 1/6 of the jar = 25 marbles, so the total jar is 150.

Hope that makes sense!

-t
kpkanupriyakhmi
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Re: FDPs Guide, 1.5a rounding

by kpkanupriyakhmi Wed Mar 04, 2015 6:04 am

My Q on page 144 Ch 7 book 2:-Fractions, Decimals and percentages is :-
a is hundredth digit of b, which is equal to 1.5a4.
Qty A:-
b rounded to nearest hundredth
Qty B:-
b rounded to nearest tenth.
tommywallach
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FDPs Guide, 1.5a rounding

by tommywallach Sun Mar 08, 2015 9:10 pm

Hey KP,

Aha. Maybe an old edition of the book. This question has been asked before, but here we go:

Anyway, we don't know what a is, so let's imagine two situations:

b = 1.514
b = 1.594

Quantity A: If we round b to nearest hundredth, our two possibilities are 1.51 and 1.59

Quantity B: If we round b to the nearest tenth, our two posibilities are 1.5 and 1.6

As you can see, we can't tell which column is bigger.

-t