Subtract 5/8 from 42/30, Solve 1 12/30

Subtract 5/8 from 42/30

1^st number: 1 12/30, 2^nd number: 5/8

42/30 - 5/8 is 31/40.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 30 × 4 = 120,
42/30 = 42 × 4/30 × 4 = 168/120
Likewise, for the 2nd fraction, since 8 × 15 = 120,
5/8 = 5 × 15/8 × 15 = 75/120
Subtract the two like fractions:
168/120 - 75/120 = 168 - 75/120 = 93/120
After reducing the fraction, the answer is 31/40

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