A 5 lb. bag of potatoes this week is $3.50. Last week, it cost $2.75.

What is the percent change?

0.21

Step-by-step explanation:

to find the percent change of something you must subtract the new-old divided by the original price.

$3.50-$2.75 = 0.75

0.75:3.50

0.2142857142857143‬

so we round and get

0.21