Subtract 42/18 from 45/21
1st number: 2 3/21, 2nd number: 2 6/18
45/21 - 42/18 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
45/21 = 45 × 6/21 × 6 = 270/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126 - Subtract the two like fractions:
270/126 - 294/126 = 270 - 294/126 = -24/126 - After reducing the fraction, the answer is -4/21
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