Subtract 63/14 from 21/30, Solve 21/30

Subtract 63/14 from 21/30

1^st number: 21/30, 2^nd number: 4 7/14

21/30 - 63/14 is -19/5.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 14 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210
Likewise, for the 2nd fraction, since 14 × 15 = 210,
63/14 = 63 × 15/14 × 15 = 945/210
Subtract the two like fractions:
147/210 - 945/210 = 147 - 945/210 = -798/210
After reducing the fraction, the answer is -19/5

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