Question

Joshua mows his neighbors' yards to earn money during the summer. He charges $20.00 per

hour because the amount of time he spends mowing depends on the size of the yard.
Joshua has to pay for the gas that his lawnmower uses, which costs him $2.50 per hour on
average. He also saves $10.00 from each job to cover the costs of keeping his lawnmower in
good working condition.
Joshua's profit is the total amount of money that he collects from a lawn mowing job that
takes t hours minus his costs.
Joshua earned a profit of $60.00 on his last lawn mowing job.

Write an equation that can be
solved to find how many hours Joshua spent mowing to earn a profit of $60.00.
In your own words, describe each part of your equation (the two expressions that are equal
as well as each term of each expression) and explain why each term is a quantity measured in
dollars.

Answer 1

The equation to find how many hours Joshua spent mowing to earn a profit of $60 is:

20t - (2.5t + 10) = 60

where t represents the number of hours Joshua spent mowing.

In this equation, 20t represents the amount of money Joshua earned by charging $20 per hour and spending t hours mowing. The term (2.5t + 10) represents the costs he incurred, which includes the cost of gas, which is $2.50 per hour on average, multiplied by the number of hours he spent mowing, plus $10 he saves from each job to cover the costs of keeping his lawnmower in good working condition.

The equal sign in the middle of the equation indicates that these two expressions have to balance out to Joshua's net profit on the last lawn mowing job, which is $60.00.

Each term in the equation is a quantity measured in dollars. The 20t and (2.5t + 10) terms both represent the amount of money earned and spent, respectively. The final term, 60, represents the net profit that Joshua earned from the job.

Explanation: