Subtract 21/84 from 42/80
42/80 - 21/84 is 11/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 84 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Likewise, for the 2nd fraction, since 84 × 20 = 1680,
21/84 = 21 × 20/84 × 20 = 420/1680 - Subtract the two like fractions:
882/1680 - 420/1680 = 882 - 420/1680 = 462/1680 - After reducing the fraction, the answer is 11/40
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