Subtract 7/30 from 42/40, Solve 1 2/40

Subtract 7/30 from 42/40

1^st number: 1 2/40, 2^nd number: 7/30

42/40 - 7/30 is 49/60.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
42/40 = 42 × 3/40 × 3 = 126/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
7/30 = 7 × 4/30 × 4 = 28/120
Subtract the two like fractions:
126/120 - 28/120 = 126 - 28/120 = 98/120
After reducing the fraction, the answer is 49/60

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