Chapter 6.3, Problem 40PFA

To determine

To find the allowance money that Kayla earned

Answer to Problem 40PFA

$50

Explanation of Solution

Given:

In June, Kayla spent all of the $80 she earned.

Difference between allowance in June and Money left over from May: $20

Calculation:

Let x be the allowance in June.

Let y be the remaining money in May.

Given that Kayla spent all of the $80 she earned.

  $\Rightarrow x+y=\mathrm{80..................}(1)$

The money that Kayla spent in June is June’s allowance and the remaining money in May.

Also, given that the difference between her allowance in June and the remaining money in May is $20.

  $\Rightarrow x-y=\mathrm{20..................}(2)$

Adding equation (1) and equation (2),

  $\begin{array}{l}\Rightarrow (x+y)+(x-y)=80+20\\ \Rightarrow 2x=100\\ \Rightarrow x=50\end{array}$

Conclusion:

Therefore, Kayla earned $50 as allowance in June.