Subtract 80/42 from 70/63, Solve 1 7/63

Subtract 80/42 from 70/63

1^st number: 1 7/63, 2^nd number: 1 38/42

70/63 - 80/42 is -50/63.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 42 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 63 × 2 = 126,
70/63 = 70 × 2/63 × 2 = 140/126
Likewise, for the 2nd fraction, since 42 × 3 = 126,
80/42 = 80 × 3/42 × 3 = 240/126
Subtract the two like fractions:
140/126 - 240/126 = 140 - 240/126 = -100/126
After reducing the fraction, the answer is -50/63

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