Before noon on Wednesday, there was a certain number of hex

[BTGmoderatorLU]

Source: Magoosh

Before noon on Wednesday, there was a certain number of hex nuts in a bin. After delivery at noon that day, the number of hex nuts in the bin increased by 30%. Which of the following could be the number of hex nuts in the bin after that delivery?

A. 5100
B. 5200
C. 5400
D. 5500
E. 5600

The OA is B

[Brent@GMATPrepNow]

Source: Magoosh

Before noon on Wednesday, there was a certain number of hex nuts in a bin. After delivery at noon that day, the number of hex nuts in the bin increased by 30%. Which of the following could be the number of hex nuts in the bin after that delivery?

A. 5100
B. 5200
C. 5400
D. 5500
E. 5600

The OA is B

Let x = number of nuts BEFORE noon
So, x + (30% of x) =number of nuts AFTER noon
In other words, 1.3x = number of nuts AFTER noon

Now check the answer choices.....
A. 5100
This means 1.3x = 5100
If we divide both sides by 1.3, we get: x = 5100/1.3 = 3923.0769...
This means there were 3923.0769... hex nuts BEFORE noon.
Since the number of hex nuts must be a positive INTEGER, answer choice A is no good.

NOTE: The correct answer must be divisible by 1.3

Scan the answers......
B. 5200 = 13 x 400
So, 5200/1.3 = 4000 (a positive integer)
PERFECT!!

Answer: B

Cheers,
Brent

[Scott@TargetTestPrep]

Source: Magoosh

Before noon on Wednesday, there was a certain number of hex nuts in a bin. After delivery at noon that day, the number of hex nuts in the bin increased by 30%. Which of the following could be the number of hex nuts in the bin after that delivery?

A. 5100
B. 5200
C. 5400
D. 5500
E. 5600

The OA is B

If there were x hex nuts before the delivery, then there are 1.3x hex nuts after the delivery. Of all the numbers in the answer choices, only 5200 will make x an integer when 1.3x is set equal to:

1.3x = 5200

x = 5200/1.3 = 4000

Answer: B