Subtract 21/90 from 3/15
3/15 - 21/90 is -1/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
3/15 = 3 × 6/15 × 6 = 18/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
18/90 - 21/90 = 18 - 21/90 = -3/90 - After reducing the fraction, the answer is -1/30
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