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