Subtract 3/8 from 70/42, Solve 1 28/42

Subtract 3/8 from 70/42

1^st number: 1 28/42, 2^nd number: 3/8

70/42 - 3/8 is 31/24.

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,
3/8 = 3 × 21/8 × 21 = 63/168
Subtract the two like fractions:
280/168 - 63/168 = 280 - 63/168 = 217/168
After reducing the fraction, the answer is 31/24
In mixed form: 17/24

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