Question

Walter and Brian each have a CD collection.

• The number of CDs in Walter’s collection can be represented by x.
• The number of CDs in Brian’s collection is 3 times the number in Walter’s collection.
• The total number of CDs in both collections is 144.
What is x, the number of CDs in Walter’s collection?
F 108
G 48
H 72
J 36

Answer 1

Option "J" 36

Explanation:

Given: The number of CDs in Walter’s collection can be represented by x.

The number of CDs in Brian’s collection is 3 times the number in Walter’s collection. The total number of CDs in both collections is 144.

To find: The value of x, the number of CDs in Walter’s collection.

Solution: The total number of CDs in both collections is 144.

The number of CDs in Walter’s collection is x.

The number of CDs in Brian’s collection is 3x.

As per question,

`3x+x=144`

`\implies4x=144`

`\implies x=(144)/(4)`

`\implies x=36`

Hence, there are 36 CDs in Walter’s collection.

So, option "J" 36 is correct.

Answer 2

The number of CDs in Walter’s collection = x
The number of CDs in Brian’s collection = 3x
The total number of CDs in both collections = 144
Then
x + 3x = 144
4x = 144
x = 36

From the above deduction, we can conclude that the correct option among all the options that are given in the question is the last option or option "J".