Subtract 42/80 from 21/28
21/28 - 42/80 is 9/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 28 × 20 = 560,
21/28 = 21 × 20/28 × 20 = 420/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
42/80 = 42 × 7/80 × 7 = 294/560 - Subtract the two like fractions:
420/560 - 294/560 = 420 - 294/560 = 126/560 - After reducing the fraction, the answer is 9/40
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