Subtract 3/30 from 42/40, Solve 1 2/40

Subtract 3/30 from 42/40

1^st number: 1 2/40, 2^nd number: 3/30

42/40 - 3/30 is 19/20.

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,
3/30 = 3 × 4/30 × 4 = 12/120
Subtract the two like fractions:
126/120 - 12/120 = 126 - 12/120 = 114/120
After reducing the fraction, the answer is 19/20

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