Please help with this easy fraction problem <3

18 + 7/9

14 + 7/8

First, rewrite each fraction in terms of a common denominator. 8 and 9 don't share a common multiple until 8 * 9 = 72, so we have

7/9 = (7/9) • (8/8) = (7 • 8)/(9 • 8) = 56/72

7/8 = (7/8) • (9/9) = (7 • 9)/(8 • 9) = 63/72

Next, write each whole number in terms of fractions with the same denominator. We have

18 • 72 = 1296  ==>  18 = 1296/72

14 • 72 = 1008  ==>  14 = 1008/72

Write each mixed number as an improper fraction:

18 + 7/9 = 1296/72 + 56/72 = (1296 + 56)/72 = 1352/72

14 + 7/8 = 1008/72 + 63/72 = (1008 + 63)/72 = 1071/72

If the backpack and book together weigh 18 + 7/9 pounds, and the backpack without the book weighs 14 + 7/8 pounds, then the book alone weighs the difference, call it b :

b = (18 + 7/9) - (14 + 7/8)

b = 1352/72 - 1071/72

b = (1352 - 1071)/72

b = 281/72

Convert this to a mixed number. 72 • 4 = 288, so 72 • 4 - 7 = 281:

b = (72 • 4 - 7)/72

b = (72 • 4)/72 - 7/72

b = 4 - 7/72

b = (3 + 1) - 7/72

b = 3 + (1 - 7/72)

b = 3 + 65/72

fist on the left goes with the third on the right. second on the left goes with the fourth on the right. third on the left goes with the second on the right. the fourth on the left goes with first on the right