The number of hours is an illustration of a unit rates
Jack earns $120, when he works for 8 hours.
Represent the unit rate with h.
So, his last week earning is represented as:
[tex]\mathbf{15h = 225}[/tex]
Divide both sides by 15, to calculate the unit rate
[tex]\mathbf{h = 15}[/tex]
When he works for 8 hours, his earnings is:
[tex]\mathbf{Earnings = 8h}[/tex]
So, we have:
[tex]\mathbf{Earnings = 8 \times 15}[/tex]
[tex]\mathbf{Earnings = 120}[/tex]
Hence, Jack earns $120, when he works for 8 hours.
Read more about unit rates at:
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