Subtract 42/30 from 18/20
1st number: 18/20, 2nd number: 1 12/30
18/20 - 42/30 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 20 × 3 = 60,
18/20 = 18 × 3/20 × 3 = 54/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
42/30 = 42 × 2/30 × 2 = 84/60 - Subtract the two like fractions:
54/60 - 84/60 = 54 - 84/60 = -30/60 - After reducing the fraction, the answer is -1/2
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