Subtract 20/40 from 28/42
28/42 - 20/40 is 1/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
28/42 = 28 × 20/42 × 20 = 560/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840 - Subtract the two like fractions:
560/840 - 420/840 = 560 - 420/840 = 140/840 - After reducing the fraction, the answer is 1/6
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