Subtract 20/42 from 25/15, Solve 1 10/15

Subtract 20/42 from 25/15

1^st number: 1 10/15, 2^nd number: 20/42

25/15 - 20/42 is 25/21.

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,
25/15 = 25 × 14/15 × 14 = 350/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210
Subtract the two like fractions:
350/210 - 100/210 = 350 - 100/210 = 250/210
After reducing the fraction, the answer is 25/21
In mixed form: 14/21

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