Subtract 21/7 from 16/30, Solve 16/30

Subtract 21/7 from 16/30

1^st number: 16/30, 2^nd number: 3 0/7

16/30 - 21/7 is -37/15.

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,
16/30 = 16 × 7/30 × 7 = 112/210
Likewise, for the 2nd fraction, since 7 × 30 = 210,
21/7 = 21 × 30/7 × 30 = 630/210
Subtract the two like fractions:
112/210 - 630/210 = 112 - 630/210 = -518/210
After reducing the fraction, the answer is -37/15

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