The combined length of 3 pieces of a board is 147 inches. the lengths of the pieces are in the ratio 5:7:9. what is the difference in inches between the longest piece and the shortest piece?

28 inches

Step-by-step explanation:

The three pieces are in the ratio

5:7:9

Multiply each piece by x

5x : 7x: 9x

Add the pieces together

5x+7x+9x = 147

Combine like terms

21x = 147

Divide each side by 21

21x/21 =147/21

x =7

The smallest piece is 5x = 5*7 =35

The largest piece is 9x = 9*7 =63

The difference is 63-35=28