Help needed for OG 13 question # 57

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Help needed for OG 13 question # 57

by sanaa.rizwan » Sat Nov 10, 2012 1:05 pm
Company P has 15% more employees in December than it had in January, If company P had 460 employees in December, how many employees did it have in January?

This is how I am solving this question

15/100 x 460 = 69

460 - 69 = 391

The correct answer is 400, How is this possible?
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by minkathebest » Sat Nov 10, 2012 3:35 pm
I am not sure where you get 69 from but draw a chart on this one to help you.

Let January Employees = x
then, December: (1.15)x

Given, employees in december = 460

So, 1.15x = 460. Solve for x, x = (460)/(1.15) = 400.



sanaa.rizwan wrote:Company P has 15% more employees in December than it had in January, If company P had 460 employees in December, how many employees did it have in January?

This is how I am solving this question

15/100 x 460 = 69

460 - 69 = 391

The correct answer is 400, How is this possible?

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by sanaa.rizwan » Sat Nov 10, 2012 3:45 pm
15% of 460 is 69
since January has 15% less employees than December, so its 460-69 = 391

thanks for your reply :)

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by minkathebest » Sat Nov 10, 2012 3:55 pm
Ah, ok, yea so you are doing it wrong. The 15 % increase is on the January employees, and NOT on the December employees.

Here is another way to look at it:

Let's say Jan = 100 and Dec = 115 (i.e., 15% increase in december)

How would you solve this if you did not know the 100 in January?

We can not do (15/100) * 115 = because you will be calculating 15 % of a number that is higher than the original number.

We do 115 = (1.15) * (# in Jan) and solve for # in Jan



sanaa.rizwan wrote:15% of 460 is 69
since January has 15% less employees than December, so its 460-69 = 391

thanks for your reply :)

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by sanaa.rizwan » Sat Nov 10, 2012 4:04 pm
Oh, i c, got it now, thanks for your time:)