Subtract 8/21 from 80/30, Solve 2 20/30

Subtract 8/21 from 80/30

1^st number: 2 20/30, 2^nd number: 8/21

80/30 - 8/21 is 16/7.

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

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 30 × 7 = 210,
80/30 = 80 × 7/30 × 7 = 560/210
Likewise, for the 2nd fraction, since 21 × 10 = 210,
8/21 = 8 × 10/21 × 10 = 80/210
Subtract the two like fractions:
560/210 - 80/210 = 560 - 80/210 = 480/210
After reducing the fraction, the answer is 16/7
In mixed form: 22/7

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