Question

The given table shows the number of pairs of shoes Lisa bought and the cost of the shoes. Find the cost of a single pair of shoes if the number of pairs bought (n) and the cost (c) are in a proportional relation.

Cost "c" $($in $\$)$	$700$	$900$	$1300$
Number of pairs bought "n"	$35$	$45$	$65$

• A. $\$0.001$
• B. $\$20$
• C. Unit rate is not constant
• D. $\$22$

Answer 1

The correct option is B $\$20$

From the table, let us check whether the ratio of the cost of the shoes to the number of pairs (i.e., unit rate) is constant.
$\frac{700}{35}=20,\frac{900}{45}=20,\frac{900}{45}=20$
Hence, the number of pairs bought (n) and the cost (c) are in a proportional relation and the unit rate, i.e., cost per pair of shoes is $\$20$ per pair.