Subtract 12/18 from 15/7, Solve 2 1/7

Subtract 12/18 from 15/7

1^st number: 2 1/7, 2^nd number: 12/18

15/7 - 12/18 is 31/21.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 7 × 18 = 126,
15/7 = 15 × 18/7 × 18 = 270/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
12/18 = 12 × 7/18 × 7 = 84/126
Subtract the two like fractions:
270/126 - 84/126 = 270 - 84/126 = 186/126
After reducing the fraction, the answer is 31/21
In mixed form: 110/21

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