Thank you for your help!!! I got it now!

Hello Everyone!!!
I have jus strtd preparing for GMAt & facing a major conceptual error (OG 13 PS Q.123)
My approach:
Mary's income = 1.6 Tim's
Juan's income = 1.4 Tim's (Tim's income 40% less than juan so juan's is 40% more than Tim)
therefor mary's income as % of juan = (1.6T/1.4T)*100 = 114%
which is not the right answer

Please help!!!!!!!!!

Thank You Brent, u saved me from a big blunder!!!!!

Hello Brent,

So if Mary's income is $160 and Tim's income is $140, given those numbers how much did Juan make? I'm still a little confused with the question.

Please help.

Brent@GMATPrepNow wrote:

atikjain wrote:Hello Everyone!!!
I have jus strtd preparing for GMAt & facing a major conceptual error (OG 13 PS Q.123)
My approach:
Mary's income = 1.6 Tim's
Juan's income = 1.4 Tim's (Tim's income 40% less than juan so juan's is 40% more than Tim)
therefor mary's income as % of juan = (1.6T/1.4T)*100 = 114%
which is not the right answer

Please help!!!!!!!!!

The problem is highlighted above in blue.

A lot of people make the conclusion that, if Tim's income is 40% less than Juan, then Juan's income is 40% more than Tim's.

Consider this scenario:
Tim's income = $60
Juan's income = $100
As you can see, Tim's income is 40% less than Juan's income. However, Juan's income is not 40% more than Tim's. In fact, Juan's income is 66 2/3% more than Tim's.

Here's another example that really illustrates the problem:
Tim's income = $50
Juan's income = $100
In this example, Tim's income is 50% less than Juan's income. However, Juan's income is not 50% more than Tim's. In fact, Juan's income is 100% more than Tim's.

Cheers,
Brent

Autumnflower wrote:Hello guys. I am currently calculating one task on page 153 nr.8
8. When 1/10 percent of 5.000 is substracted from 1/10 of 5.000, the difference is.
a) 0
b) 50
c) 450
d) 495
e) 500

I calculated like this way: 1/10 of 5000 is 500 and when it is substracted from the same amount it is 500-500 equals 0.

When I just looked it up it says the correct answer is e).
The solution from GMAT is: Since 1/10 percent is 1/1000, the difference asked for is (1/10)(5,000)- (1/1,000)(5,000)= 500-5=495

I dont get this fraction of 1/1000.
I would apprecitae any help.

Thank you!

Solution:

We can break this problem into two parts:

1) What is 1/10 percent of 5,000?

2) What is 1/10 of 5,000?

Let's start with part 1.

To calculate 1/10 percent of 5,000 we must first remember to DIVIDE 1/10 BY 100.

So we have: (1/10)/(100)

To divide a number by 100 means to multiply it by 1/100, so we have:

1/10 x 1/100 = 1/1,000

Thus, 1/10 percent of 5,000 = 1/1,000 x 5,000 = 5.

(Note: If dividing 1/10 by 100 was confusing, consider a simpler example. Say we were asked for 20% of a number. Well, to get 20% as a fraction, we would divide 20 by 100. So 20% is 20/100, or 1/5.)

Now let's concentrate on part 2. We need to calculate 1/10 of 5,000. To do this we simply multiply 1/10 by 5,000.

1/10 x 5,000 = 500

The answer to part 1 is 5, and the answer to part 2 is 500. Their difference is 500 - 5 = 495.

The answer is D