Subtract 21/24 from 42/80
42/80 - 21/24 is -7/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 24 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240 - Likewise, for the 2nd fraction, since 24 × 10 = 240,
21/24 = 21 × 10/24 × 10 = 210/240 - Subtract the two like fractions:
126/240 - 210/240 = 126 - 210/240 = -84/240 - After reducing the fraction, the answer is -7/20
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