Subtract 48/30 from 21/70, Solve 21/70

Subtract 48/30 from 21/70

1^st number: 21/70, 2^nd number: 1 18/30

21/70 - 48/30 is -13/10.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
48/30 = 48 × 7/30 × 7 = 336/210
Subtract the two like fractions:
63/210 - 336/210 = 63 - 336/210 = -273/210
After reducing the fraction, the answer is -13/10

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