Subtract 4/20 from 70/42, Solve 1 28/42

Subtract 4/20 from 70/42

1^st number: 1 28/42, 2^nd number: 4/20

70/42 - 4/20 is 22/15.

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,
4/20 = 4 × 21/20 × 21 = 84/420
Subtract the two like fractions:
700/420 - 84/420 = 700 - 84/420 = 616/420
After reducing the fraction, the answer is 22/15
In mixed form: 17/15

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