Subtract 9/7 from 15/18, Solve 15/18

Subtract 9/7 from 15/18

1^st number: 15/18, 2^nd number: 1 2/7

15/18 - 9/7 is -19/42.

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,
15/18 = 15 × 7/18 × 7 = 105/126
Likewise, for the 2nd fraction, since 7 × 18 = 126,
9/7 = 9 × 18/7 × 18 = 162/126
Subtract the two like fractions:
105/126 - 162/126 = 105 - 162/126 = -57/126
After reducing the fraction, the answer is -19/42

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