Subtract 50/42 from 72/70, Solve 1 2/70

Subtract 50/42 from 72/70

1^st number: 1 2/70, 2^nd number: 1 8/42

72/70 - 50/42 is -17/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
72/70 = 72 × 3/70 × 3 = 216/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
50/42 = 50 × 5/42 × 5 = 250/210
Subtract the two like fractions:
216/210 - 250/210 = 216 - 250/210 = -34/210
After reducing the fraction, the answer is -17/105

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