Subtract 2/21 from 21/18, Solve 1 3/18

Subtract 2/21 from 21/18

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

21/18 - 2/21 is 15/14.

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,
21/18 = 21 × 7/18 × 7 = 147/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
2/21 = 2 × 6/21 × 6 = 12/126
Subtract the two like fractions:
147/126 - 12/126 = 147 - 12/126 = 135/126
After reducing the fraction, the answer is 15/14
In mixed form: 11/14

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