Subtract 21/48 from 42/90
42/90 - 21/48 is 7/240.
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,
42/90 = 42 × 8/90 × 8 = 336/720 - Likewise, for the 2nd fraction, since 48 × 15 = 720,
21/48 = 21 × 15/48 × 15 = 315/720 - Subtract the two like fractions:
336/720 - 315/720 = 336 - 315/720 = 21/720 - After reducing the fraction, the answer is 7/240
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