Subtract 21/90 from 15/30
15/30 - 21/90 is 4/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 90 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
15/30 = 15 × 3/30 × 3 = 45/90 - Likewise, for the 2nd fraction, since 90 × 1 = 90,
21/90 = 21 × 1/90 × 1 = 21/90 - Subtract the two like fractions:
45/90 - 21/90 = 45 - 21/90 = 24/90 - After reducing the fraction, the answer is 4/15
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