Subtract 49/30 from 10/21, Solve 10/21

Subtract 49/30 from 10/21

1^st number: 10/21, 2^nd number: 1 19/30

10/21 - 49/30 is -81/70.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
10/21 = 10 × 10/21 × 10 = 100/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
49/30 = 49 × 7/30 × 7 = 343/210
Subtract the two like fractions:
100/210 - 343/210 = 100 - 343/210 = -243/210
After reducing the fraction, the answer is -81/70

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