Answer:
Arla - $15, Kal - $17.5
Step-by-step explanation:
Let $x be Arla's hourly wage and $y be Kal's hourly wage.
1. In the first week on the job they each worked 40 hours and earned $(40x+40y) together. Their total earnings were $1300, so
40x+40y=1300.
2. In the second week on the job business was slow so Arla worked 20 hours and earned $20x, Kal worked 16 hours and earned $16y, $(20x+16y) in total. Their total pool earning was $580, so
20x+16y=580.
3. Solve the system of two equations:
[tex]\left\{\begin{array}{l}40x+40y=1300\\20x+16y=580\end{array}\right.\Rightarrow \left\{\begin{array}{l}40x+40y=1300\\40x+32y=1160\end{array}\right..[/tex]
Subtract them:
[tex]40y-32y=1300-1160,\\ \\8y=140,\\ \\y=\$17.5.[/tex]
Then
[tex]40x+40\cdot 17.5=1300,\\ \\40x=1300-700,\\ \\40x=600,\\ \\x=\$15.[/tex]