Subtract 15/42 from 21/10, Solve 2 1/10

Subtract 15/42 from 21/10

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

21/10 - 15/42 is 61/35.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
21/10 = 21 × 21/10 × 21 = 441/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
15/42 = 15 × 5/42 × 5 = 75/210
Subtract the two like fractions:
441/210 - 75/210 = 441 - 75/210 = 366/210
After reducing the fraction, the answer is 61/35
In mixed form: 126/35

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