Subtract 40/7 from 80/18, Solve 4 8/18

Subtract 40/7 from 80/18

1^st number: 4 8/18, 2^nd number: 5 5/7

80/18 - 40/7 is -80/63.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 7 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
80/18 = 80 × 7/18 × 7 = 560/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
40/7 = 40 × 18/7 × 18 = 720/126
Subtract the two like fractions:
560/126 - 720/126 = 560 - 720/126 = -160/126
After reducing the fraction, the answer is -80/63

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