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

Subtract 21/7 from 7/30

1^st number: 7/30, 2^nd number: 3 0/7

7/30 - 21/7 is -83/30.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 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 7 × 30 = 210,
21/7 = 21 × 30/7 × 30 = 630/210
Subtract the two like fractions:
49/210 - 630/210 = 49 - 630/210 = -581/210
After reducing the fraction, the answer is -83/30

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