Subtract 60/20 from 70/42, Solve 1 28/42

Subtract 60/20 from 70/42

1^st number: 1 28/42, 2^nd number: 3 0/20

70/42 - 60/20 is -4/3.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
70/42 = 70 × 10/42 × 10 = 700/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
60/20 = 60 × 21/20 × 21 = 1260/420
Subtract the two like fractions:
700/420 - 1260/420 = 700 - 1260/420 = -560/420
After reducing the fraction, the answer is -4/3

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