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

Subtract 42/25 from 15/18

1^st number: 15/18, 2^nd number: 1 17/25

15/18 - 42/25 is -127/150.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 25 is 450

Next, find the equivalent fraction of both fractional numbers with denominator 450
For the 1st fraction, since 18 × 25 = 450,
15/18 = 15 × 25/18 × 25 = 375/450
Likewise, for the 2nd fraction, since 25 × 18 = 450,
42/25 = 42 × 18/25 × 18 = 756/450
Subtract the two like fractions:
375/450 - 756/450 = 375 - 756/450 = -381/450
After reducing the fraction, the answer is -127/150

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