Subtract 18/48 from 21/90
21/90 - 18/48 is -17/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 48 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 48 × 15 = 720,
18/48 = 18 × 15/48 × 15 = 270/720 - Subtract the two like fractions:
168/720 - 270/720 = 168 - 270/720 = -102/720 - After reducing the fraction, the answer is -17/120
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