Subtract 21/18 from 7/15
1st number: 7/15, 2nd number: 1 3/18
7/15 - 21/18 is -7/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
7/15 = 7 × 6/15 × 6 = 42/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Subtract the two like fractions:
42/90 - 105/90 = 42 - 105/90 = -63/90 - After reducing the fraction, the answer is -7/10
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