Question

Write the inequality for the following: A prom ticket for acouple at Smith High school is $120. Tom is going tosave money for the ticket by walking his neighbor's dogfor $15 per week. If Tom already has saved $21, what isthe minimum number of weeks Tom must walk the dogto earn enough to pay for the prom ticket?

Answer 1

We are given that Tom earns 15 per week and that he already has 21. If "x" is the number of week, then his earnings are given by:

$21+15x$

Since the minimum he must save is 120 then the earning must be greater or equal to that, therefore:

$21+15x\ge120$

To solve for "x" we need to subtract 21 to both sides:

$\begin{gathered} 15x\ge120-21 \\ 15x\ge99 \end{gathered}$

dividing both sides by 15:

$x\ge\frac{99}{15}$

Solving the operation:

$x\ge6.6$

Therefore, he needs to work for at least 6.6 weeks