Answer:
13 hours
Explanation:
Since Shawn mows lawns at a rate of 5 dollars an hour, if he mows for t hours, he earns 5t dollars. Also, he gets 10 dollars weekly allowance from his parents. Thus, the total amount he earns per week is thus 10 + 5t.
Since he needs to earn enough to buy 75 dollars pair of basketball shoes, the amount he earns must equal the price of the shoes. So,
10 + 5t = 75
We now solve for t to find the amount of hours if takes him to earn enough to buy the shoes.
So,
10 + 5t = 75
Subtracting 10 from both sides, we have
10 - 10 + 5t = 75 - 10
5t = 65
dividing both sides by 5, we have
t = 65/5
t = 13 hours
So, it takes Shawn 13 hours to earn enough to buy the shoes.