Subtract 50/28 from 70/21, Solve 3 7/21

Subtract 50/28 from 70/21

1^st number: 3 7/21, 2^nd number: 1 22/28

70/21 - 50/28 is 65/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
50/28 = 50 × 3/28 × 3 = 150/84
Subtract the two like fractions:
280/84 - 150/84 = 280 - 150/84 = 130/84
After reducing the fraction, the answer is 65/42
In mixed form: 123/42

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