Subtract 21/42 from 49/15, Solve 3 4/15

Subtract 21/42 from 49/15

1^st number: 3 4/15, 2^nd number: 21/42

49/15 - 21/42 is 83/30.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
49/15 = 49 × 14/15 × 14 = 686/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Subtract the two like fractions:
686/210 - 105/210 = 686 - 105/210 = 581/210
After reducing the fraction, the answer is 83/30
In mixed form: 223/30

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