Subtract 21/7 from 70/18, Solve 3 16/18

Subtract 21/7 from 70/18

1^st number: 3 16/18, 2^nd number: 3 0/7

70/18 - 21/7 is 8/9.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 7 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 7 × 18 = 126,
21/7 = 21 × 18/7 × 18 = 378/126
Subtract the two like fractions:
490/126 - 378/126 = 490 - 378/126 = 112/126
After reducing the fraction, the answer is 8/9

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