Subtract 40/56 from 20/30
20/30 - 40/56 is -1/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 30 × 28 = 840,
20/30 = 20 × 28/30 × 28 = 560/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
40/56 = 40 × 15/56 × 15 = 600/840 - Subtract the two like fractions:
560/840 - 600/840 = 560 - 600/840 = -40/840 - After reducing the fraction, the answer is -1/21
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