Subtract 90/18 from 21/15
1st number: 1 6/15, 2nd number: 5 0/18
21/15 - 90/18 is -18/5.
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,
21/15 = 21 × 6/15 × 6 = 126/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
90/18 = 90 × 5/18 × 5 = 450/90 - Subtract the two like fractions:
126/90 - 450/90 = 126 - 450/90 = -324/90 - After reducing the fraction, the answer is -18/5
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