31/125 =

Question

\frac{31}{125} =

(A) 0.248
(B) 0.252
(C) 0.284
(D) 0.312
(E) 0.320

Bunuel · Accepted Answer

SOLUTION

\frac{31}{125} =

(A) 0.248
(B) 0.252
(C) 0.284
(D) 0.312
(E) 0.320

\frac{31}{125} =\frac{31*8}{125*8} =\frac{248}{1000} =0.248 .

Answer: A.

Abdul29 · Answer

For the sake of time, we approximate 31 to 30. 30/125 = 6/25.
We multiply the fraction by 4 to get the denominator to 100 -> 24/100 = 24% = 0.24.

Since we rounded numerator down, the answer is a bit undervalued so the closest answer is (A). 0.248.

arunspanda · Answer

\frac{31}{125} =

(A) 0.248
(B) 0.252
(C) 0.284
(D) 0.312
(E) 0.320

\frac{31}{125} = \frac{31*8}{125*8} = \frac{248}{1000} = 0.248

Answer:  (A)

tarunsng · Answer

125 can simply be written as 1000/8
multiply 8 with 31 to get 248
divide it by 1000 to get .248
answer is A
simple one

sabxu1 · Answer

why do you choose to times by 8?

Bunuel · Answer

The options are in decimals. To transform a fraction to decimal the denominator must be some power of 10. 125*8 = 1000.

sabxu1 · Answer

do you times i by 8 because you want to get to an easy number such as 1000?

Bunuel · Answer

As I said, we multiply by 8 to get in the denominator some power of 10 to transform the fraction into the decimal easily.

OptimusPrepJanielle · Answer

Since the options are all in the decimal forms, we need to divide the numerator by denominator.
If we have a calculator, we can directly divide it. But since we are not allowed a calculator, we need to make our lives simpler.

Hence we try to bring denominator in a form by which the division becomes easier.
125 = 5^3
If we multiply 5^3 by 2^3, we get 10^3 or 1000 and then we can easily divide.

Hope this clarifies your doubt.

Abhishek009 · Answer

\frac{31}{125}

~ \frac{31}{124}

=\frac{1}{4}

=0.25

Thus, answer will be (A) 0.248

susheelh · Answer

In case someone is interested in a more detailed approach.

\frac{31}{125} = \frac{30}{125}+\frac{1}{125}

= \frac{6}{25}+\frac{1}{125}

= \frac{5}{25} + \frac{1}{25} + \frac{1}{125}

= \frac{1}{5}+ \frac{1}{25} + \frac{1}{125}

= 0.2 + \frac{0.2}{5}+ \frac{1}{125} = 0.2 +0.04 + \frac{1}{125} = 0.24 + \frac{1}{125}

= a little over 0.24

= Option A

Abhishek009 · Answer

\frac{31}{125}

Or,  \frac{31}{124}=\frac{1}{4} = 0.25

Since we have approximated 125 as 124, 0.25 will be slightly less than 0.25 ie, 0.248, Answer must be (A)

GmatKnightTutor · Answer

Hello, people. A good way to do this is not to do long division but to multiply instead.

A quick thing we can leverage is the fact the denominator is 125. If we notice that 125 x 8 = 1000, we can simply multiply the numerator by 8 as well - and that way know the digits involved in the decimal.

31 x 8 = 248

248/1000

(A) is your answer.

31/125 =

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

31/125 =

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards