Subtract 25/18 from 15/42, Solve 15/42

Subtract 25/18 from 15/42

1^st number: 15/42, 2^nd number: 1 7/18

15/42 - 25/18 is -65/63.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
15/42 = 15 × 3/42 × 3 = 45/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
25/18 = 25 × 7/18 × 7 = 175/126
Subtract the two like fractions:
45/126 - 175/126 = 45 - 175/126 = -130/126
After reducing the fraction, the answer is -65/63

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