Question

. Shawn gets an allowance of $18 each week and his sister Natasha gets an allowance of $9 each week. Shawn saves 1/2 of his allowance, and Natasha saves 2/3 of her allowance. Suppose Shawn started with $0 savings, and Natasha started with $30. How many weeks will it take until they have the same amount in savings?

Answer 1

Shawn and Natasha have same amount in savings after
`10` weeks.

Explanation:

Shawn gets an allowance of $18 each week.

Amount saved by Shawn =
`(1)/(2)(\$18)=\$9`

Natasha gets an allowance of $9 each week.

Amount saved by Natasha =
`(2)/(3)(\$9)=\$6`

Suppose that Shawn and Natasha have same amount in savings after
`x` weeks.

Also, Shawn started with $0 savings, and Natasha started with $30.

So,

`9x=30+6x\\9x-6x=30\\3x=30\\x=10`

Therefore,

Shawn and Natasha have same amount in savings after
`10` weeks.