Advanced GMAT Math QuestionsVersion

[rahulpatel19]

please help on this question: -

If 6 workers can build 4 cars in 2 days, then how many days would it take 8 workers to build 6 cars?

a. 5/3
b. 9/4
c. 8/3
d. 11/4
e. 10/3

[truplayer256]

Well, if 6 workers can build 4 cars in 2 days, then they can build 4 cars/ 2 days= 2 cars per day. With this said, each worker can build 2 cars/ 6 workers= 1/3 cars per day. Now, if there were 8 workers, then, all the workers together can build 1/3 * 8= 8/3 cars per day. In order to find out how many days it'd take the workers to build 6 cars, you can do (6 cars)/(8/3 cars per day)= 6 cars* 3 days/8 cars=9/4 days. B.

[gmat740]

https://www.beatthegmat.com/ratio-propor ... tml#142267

take a look please

Karan

[VP_Jim]

This is a fun one! Break it down into steps:

If 6 workers can build 4 cars in 2 days...

1. Then 6 workers can build 2 cars per day
2. And 1 worker can build 1/3 of a car per day
3. Therefore, 8 workers can do 8/3 of a car per day
4. So, to build 6 cars, 8 workers must work:

6 cars / (8/3) = 18/8 = 9/4 days

Hope this helps!

[rahulpatel19]

here is the other one: -

Marge has n candies, where n is an integer such that 20 < n< 50. If Marge divides the candies equally among 5 children, she will have 2 candies remaining. Ifshe divides the candies among 6 children, she will have 1 candy remaining. How many candies will remain if she divides the candies among 7 children?

a) 0
b) 1
c) 2
d) 3
e) 4

[mals24]

This is like a remainder question in disguise.

So the question is basically saying, n when divided by 5 leaves a remainder of 2.
n when divided by 6 leaves a remainder of 1.
what is the remainder when n is divided by 7?

n = 5a + 2
n = 6b + 1

5a + 2 = 6b + 1

6b-5a = 1

Now what are the two numbers, one which is a multiple of 6 and the other a multiple of 5, which when subtracted give the answer 1 and are between the range 20-50.

You'll get 2 values (24,25) and (35,36)
(just look for multiples of either 5 or 6 that fall within the range 20-50)

you cant take (24,25) because 24-25 = -1.

So, 5a = 35
n = 35 + 2
n = 37

37 when divided by 7 leaves a remainder of 2.

So C