Day 5 Email

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Day 5 Email

by dee949 » Sat Apr 12, 2014 6:01 pm
I don't understand the strategy to approach this question from 13th OG edition (click image to make bigger):
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I don't understand exactly what the approach is for this?

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by Brent@GMATPrepNow » Sun Apr 13, 2014 6:09 pm
What is the 25th digit to the right of the decimal point in the decimal form of 6/11?

A) 3
B) 4
C) 5
D) 6
E) 7
I'm moving this to the Problem Solving forum.

If we use LONG DIVISION and divide 6 by 11, we see a pattern emerge.
We get: 6/11 = 0.5454....
So, the 1st digit to the right of the decimal point is 5
The 2nd digit to the right of the decimal point is 4
The 3rd digit to the right of the decimal point is 5
The 4th digit to the right of the decimal point is 4
and so on...

Every ODD digit (1st, 3rd, 5th, etc) is 5
Every EVEN digit (2nd, 4th, 6th etc) is 4

So, the 25th digit will be 5

Answer: C

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by [email protected] » Sun Apr 13, 2014 11:09 pm
Hi deepti.sabbella,

The GMAT Quant section will include a number of questions that will require to convert one form of data into another. You might be asked for "unit conversions", which include minutes to seconds, dollars to cents, etc. You might also be asked to convert fractions to decimals to percents.

Here, knowing the value of 1/11 makes this question fairly straightforward.

1/11 is a "repeater"; 1/11 = .09090909etc

So 6/11 is 6 times that + .54545454etc.

Since we're asked for the 25th digit, we're asked for which digit appears in odd "spots"

Final Answer: 5 - C

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