Subtract 21/18 from 42/45
1st number: 42/45, 2nd number: 1 3/18
42/45 - 21/18 is -7/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
42/45 = 42 × 2/45 × 2 = 84/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Subtract the two like fractions:
84/90 - 105/90 = 84 - 105/90 = -21/90 - After reducing the fraction, the answer is -7/30
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