Subtract 3/8 from 42/15, Solve 2 12/15

Subtract 3/8 from 42/15

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

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

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

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 15 × 8 = 120,
42/15 = 42 × 8/15 × 8 = 336/120
Likewise, for the 2nd fraction, since 8 × 15 = 120,
3/8 = 3 × 15/8 × 15 = 45/120
Subtract the two like fractions:
336/120 - 45/120 = 336 - 45/120 = 291/120
After reducing the fraction, the answer is 97/40
In mixed form: 217/40

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