Subtract 70/20 from 1/84, Solve 1/84

Subtract 70/20 from 1/84

1^st number: 1/84, 2^nd number: 3 10/20

1/84 - 70/20 is -293/84.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
1/84 = 1 × 5/84 × 5 = 5/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
70/20 = 70 × 21/20 × 21 = 1470/420
Subtract the two like fractions:
5/420 - 1470/420 = 5 - 1470/420 = -1465/420
After reducing the fraction, the answer is -293/84

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