Subtract 7/70 from 72/42, Solve 1 30/42

Subtract 7/70 from 72/42

1^st number: 1 30/42, 2^nd number: 7/70

72/42 - 7/70 is 113/70.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
7/70 = 7 × 3/70 × 3 = 21/210
Subtract the two like fractions:
360/210 - 21/210 = 360 - 21/210 = 339/210
After reducing the fraction, the answer is 113/70
In mixed form: 143/70

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