Subtract 21/45 from 15/90
15/90 - 21/45 is -3/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
15/90 = 15 × 1/90 × 1 = 15/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Subtract the two like fractions:
15/90 - 42/90 = 15 - 42/90 = -27/90 - After reducing the fraction, the answer is -3/10
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