Answer:
No of clown sold in 2010 = 17
No of clown sold in 2015 = 39
Unit rate of change = 39 - 17/17 x 100
Unit rate of change = 129.41%
Explanation
The unit rate of change from 2010 to 2015 is equal to the number of clown sold in 2015 minus the number of clown sold in 2010 divided by the number of clown sold in 2010 multiplied by 100.