Subtract 21/70 from 12/21, Solve 12/21

Subtract 21/70 from 12/21

12/21 - 21/70 is 19/70.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210
Likewise, for the 2nd fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210
Subtract the two like fractions:
120/210 - 63/210 = 120 - 63/210 = 57/210
After reducing the fraction, the answer is 19/70

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