Subtract 42/90 from 20/56
20/56 - 42/90 is -23/210.
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,
20/56 = 20 × 45/56 × 45 = 900/2520 - Likewise, for the 2nd fraction, since 90 × 28 = 2520,
42/90 = 42 × 28/90 × 28 = 1176/2520 - Subtract the two like fractions:
900/2520 - 1176/2520 = 900 - 1176/2520 = -276/2520 - After reducing the fraction, the answer is -23/210
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