When Zack started kindergarten at age 5, he was 43 inches tall. When he graduated high school at age 18, he was 70 inches tall. Zack wanted to know the percent of change in his height over that time, so he made this calculation:
percent of change
70
43
70
0.38571
ellipsis
39%
Complete the paragraph to explain what is wrong with Zack's calculation.
Zack's calculation has an error in the . There, the number  should actually be the number . The actual percent of change in Zack's height is  than he calculated.
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