Subtract 2/20 from 21/7, Solve 3 0/7

Subtract 2/20 from 21/7

1^st number: 3 0/7, 2^nd number: 2/20

21/7 - 2/20 is 29/10.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 20 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 7 × 20 = 140,
21/7 = 21 × 20/7 × 20 = 420/140
Likewise, for the 2nd fraction, since 20 × 7 = 140,
2/20 = 2 × 7/20 × 7 = 14/140
Subtract the two like fractions:
420/140 - 14/140 = 420 - 14/140 = 406/140
After reducing the fraction, the answer is 29/10
In mixed form: 29/10

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