Subtract 15/8 from 70/42, Solve 1 28/42

Subtract 15/8 from 70/42

1^st number: 1 28/42, 2^nd number: 1 7/8

70/42 - 15/8 is -5/24.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
70/42 = 70 × 4/42 × 4 = 280/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
15/8 = 15 × 21/8 × 21 = 315/168
Subtract the two like fractions:
280/168 - 315/168 = 280 - 315/168 = -35/168
After reducing the fraction, the answer is -5/24

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