To find the amount of inches, multiply the length by the percent. A percent is 40% but can also be written as a decimal conversion as 0.4. Then 40% of 60 inches is 0.4(60)= 24 inches.
However, she didn't use all 24 inches. She used 35%. This converts to 0.35 and then multiply for 0.35(24) = 8.4 inches.
