CPM Homework Help : AC Problem 4-48

Mr. Wallis decided to create another table to figure out how much it costs to send a certain number of regular letters through the mail. Use proportional reasoning to complete his table below.

Number of Letters	Cost of Stamps
$10$	$$3.40$
$2$	$$0.68$
	$$5.10$
$7$
$1$
$500$
	$$14.28$

Hint:

First set up the proportion.

$\frac{2}{0.68}=\frac{n}{5.10}$

More Help 1:

What did you multiply $0.68$ by to get $5.10$ ?

$7.5$

Answer:

$15$ letters for $$5.10$

More Help 2:

Multiply $2$ by $7.5$ to get the number of letters. Repeat this strategy for all of the blanks within the table.

Use the eTool below to help you with this problem.
Click the link at right for the full version of the eTool: 4-48 HW eTool (Desmos)