Subtract 80/30 from 63/21, Solve 3 0/21

Subtract 80/30 from 63/21

1^st number: 3 0/21, 2^nd number: 2 20/30

63/21 - 80/30 is 1/3.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 21 × 10 = 210,
63/21 = 63 × 10/21 × 10 = 630/210
Likewise, for the 2nd fraction, since 30 × 7 = 210,
80/30 = 80 × 7/30 × 7 = 560/210
Subtract the two like fractions:
630/210 - 560/210 = 630 - 560/210 = 70/210
After reducing the fraction, the answer is 1/3

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