Dylan Nixon
2022-10-27
Answered

David charges $15 plus $5.50 per hour to mow lawns. Ari charges $12 plus $6.25 per hour to mow lawns. In what situations is Ari's charge greater than or equal to David's charge?

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Jovanni Salinas

Answered 2022-10-28
Author has **18** answers

Let x be the number of hours of lawn mowing for which Ari's charge greater than or equal to David's charge. Then $$12+6.25x\ge 15+5.5x$$ or, $$6.25x-5.5x\ge 15-12$$ or, $$0.75x\ge 3$$ or, $$\frac{3x}{4}\ge 3$$. Now, on multiplying both the sides by $$\frac{4}{3}$$ , we get $$x\ge 4$$. Thus, if the lawn mowing hours are 4 or more, then Ari's charge is greater than or equal to David's charge

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