Subtract 4/56 from 21/90
21/90 - 4/56 is 17/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 56 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 90 × 28 = 2520,
21/90 = 21 × 28/90 × 28 = 588/2520 - Likewise, for the 2nd fraction, since 56 × 45 = 2520,
4/56 = 4 × 45/56 × 45 = 180/2520 - Subtract the two like fractions:
588/2520 - 180/2520 = 588 - 180/2520 = 408/2520 - After reducing the fraction, the answer is 17/105
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