Subtract 2/40 from 42/30, Solve 1 12/30

Subtract 2/40 from 42/30

1^st number: 1 12/30, 2^nd number: 2/40

42/30 - 2/40 is 27/20.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 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 40 × 3 = 120,
2/40 = 2 × 3/40 × 3 = 6/120
Subtract the two like fractions:
168/120 - 6/120 = 168 - 6/120 = 162/120
After reducing the fraction, the answer is 27/20
In mixed form: 17/20

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