Subtract 1/21 from 70/18, Solve 3 16/18

Subtract 1/21 from 70/18

1^st number: 3 16/18, 2^nd number: 1/21

70/18 - 1/21 is 242/63.

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

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
1/21 = 1 × 6/21 × 6 = 6/126
Subtract the two like fractions:
490/126 - 6/126 = 490 - 6/126 = 484/126
After reducing the fraction, the answer is 242/63
In mixed form: 353/63

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