Subtract 90/5 from 21/15
1st number: 1 6/15, 2nd number: 18 0/5
21/15 - 90/5 is -83/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 5 is 15
Next, find the equivalent fraction of both fractional numbers with denominator 15 - For the 1st fraction, since 15 × 1 = 15,
21/15 = 21 × 1/15 × 1 = 21/15 - Likewise, for the 2nd fraction, since 5 × 3 = 15,
90/5 = 90 × 3/5 × 3 = 270/15 - Subtract the two like fractions:
21/15 - 270/15 = 21 - 270/15 = -249/15 - After reducing the fraction, the answer is -83/5
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