Subtract 49/21 from 7/30, Solve 7/30

Subtract 49/21 from 7/30

1^st number: 7/30, 2^nd number: 2 7/21

7/30 - 49/21 is -21/10.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
7/30 = 7 × 7/30 × 7 = 49/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
49/21 = 49 × 10/21 × 10 = 490/210
Subtract the two like fractions:
49/210 - 490/210 = 49 - 490/210 = -441/210
After reducing the fraction, the answer is -21/10

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