Subtract 30/18 from 45/42
1st number: 1 3/42, 2nd number: 1 12/18
45/42 - 30/18 is -25/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
45/42 = 45 × 3/42 × 3 = 135/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126 - Subtract the two like fractions:
135/126 - 210/126 = 135 - 210/126 = -75/126 - After reducing the fraction, the answer is -25/42
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