Question

You earn $\$9.20$ per hour at your summer job. Write and solve an inequality that represents the numbers of hours you can work to earn enough money to buy a smart phone that costs $\$299$.

Answer 1

Step 1 : Write the inequality

Given :

$$\begin{gathered} \mathrm{Earning}\mathrm{per}\mathrm{hour}=\$9.20 \\ \mathrm{Smartphone}\mathrm{cost}=\$299 \end{gathered}$$

Let, the number of hours worked be $\$x$.

Now, according the the question

Required inequality is $9.20x\ge 299$

Step 2 : Solve the inequality

$$\begin{gathered} \Rightarrow 9.20x\ge 299 \\ \Rightarrow x\ge \frac{299}{9.20} \\ \therefore x\ge 32.5hours \end{gathered}$$

Hence, you can work at least $32.5\mathrm{hours}$ to buy a smartphone costs $\$299$.