Subtract 3/21 from 12/5, Solve 2 2/5

Subtract 3/21 from 12/5

1^st number: 2 2/5, 2^nd number: 3/21

12/5 - 3/21 is 79/35.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
12/5 = 12 × 21/5 × 21 = 252/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
3/21 = 3 × 5/21 × 5 = 15/105
Subtract the two like fractions:
252/105 - 15/105 = 252 - 15/105 = 237/105
After reducing the fraction, the answer is 79/35
In mixed form: 29/35

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