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decimal in fraction

Got stuck today in a case when I had to divide decimals. Not the best with math and haven't practiced this much. 

Got presented with this = .024/.8

I know what you're thinking, this guy is dumb. I knew my answer would be some variation of 3 but didn't know where to put the decimal place.

Thanks

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Top answer
Vlad
Coach
on Nov 09, 2018
McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School

Hi,

Just put all the numbers as the powers of 10:

0.024/0.8 = 24 * 10^(-3) / 8*10^(-1)= 3*10^(-2)

Best!

on Nov 08, 2018

In order to get non-decimal number, you have to move to right the decimal point until you get a non-decimal number. Basically you need to count how many digits you have at the right of the decimal point. Obviously must move the decimal point to the denominator as well. 

Example:

.024 (3 digits at the right of the decimal point) * 1000 = 24 --> .8 * 1000 (same factor of numerator) = 8000

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Deleted
Coach
on Nov 08, 2018

hey there, two rules to remember with decimals and division:

1) if you move both decimals in the answer direction, the answer is the same. For example, 0.02/0.08=0.2/0.8=2/8=20/80

2) If you only move one of the decimals, you have to move it back at the end (e.g. if you moved the decimal right, you have to move it back left, or vice versa.

In your example, I would do:

0.024/0.8 =0.24/8

0.24/8 --> move decimal on left to the right by 2 units so 24/8 = 3

at the end, move the decimal back to the left by 2 units, so 3--> 0.03

so the answer is 0.03.

Hope that makes sense!

on Nov 09, 2018

Whenevre you got stuck like this a simple solution is to mulitply with powers of 10.

0.24/0.8 = 24*10/8*100 

we know 0.24 = 24/100 

We also know 0.8= 8/10, 1/0.8=10/8 

Multiply the power of 10 in numerator which is equal to number of decimals in denominator.

Multiply the power of 10 in denominator which is equal to number of decimals in numerator..

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