Subtract 42/30 from 7/8, Solve 7/8 - 1 12/30 as a fraction

Subtract 42/30 from 7/8

1^st number: 7/8, 2^nd number: 1 12/30

7/8 - 42/30 is -21/40.

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

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 8 × 15 = 120,
7/8 = 7 × 15/8 × 15 = 105/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
42/30 = 42 × 4/30 × 4 = 168/120
Subtract the two like fractions:
105/120 - 168/120 = 105 - 168/120 = -63/120
After reducing the fraction, the answer is -21/40

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