Subtract 12/24 from 70/21, Solve 3 7/21

Subtract 12/24 from 70/21

1^st number: 3 7/21, 2^nd number: 12/24

70/21 - 12/24 is 17/6.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
70/21 = 70 × 8/21 × 8 = 560/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
12/24 = 12 × 7/24 × 7 = 84/168
Subtract the two like fractions:
560/168 - 84/168 = 560 - 84/168 = 476/168
After reducing the fraction, the answer is 17/6
In mixed form: 25/6

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