Subtract 12/36 from 90/21, Solve 4 6/21

Subtract 12/36 from 90/21

1^st number: 4 6/21, 2^nd number: 12/36

90/21 - 12/36 is 83/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 21 × 12 = 252,
90/21 = 90 × 12/21 × 12 = 1080/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
12/36 = 12 × 7/36 × 7 = 84/252
Subtract the two like fractions:
1080/252 - 84/252 = 1080 - 84/252 = 996/252
After reducing the fraction, the answer is 83/21
In mixed form: 320/21

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