Subtract 4/18 from 75/21, Solve 3 12/21

Subtract 4/18 from 75/21

1^st number: 3 12/21, 2^nd number: 4/18

75/21 - 4/18 is 211/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
75/21 = 75 × 6/21 × 6 = 450/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
4/18 = 4 × 7/18 × 7 = 28/126
Subtract the two like fractions:
450/126 - 28/126 = 450 - 28/126 = 422/126
After reducing the fraction, the answer is 211/63
In mixed form: 322/63

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