Subtract 42/15 from 3/8, Solve 3/8 - 2 12/15 as a fraction

Subtract 42/15 from 3/8

1^st number: 3/8, 2^nd number: 2 12/15

3/8 - 42/15 is -97/40.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 15 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 8 × 15 = 120,
3/8 = 3 × 15/8 × 15 = 45/120
Likewise, for the 2nd fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120
Subtract the two like fractions:
45/120 - 336/120 = 45 - 336/120 = -291/120
After reducing the fraction, the answer is -97/40

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