Subtract 42/80 from 21/60
21/60 - 42/80 is -7/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 60 × 4 = 240,
21/60 = 21 × 4/60 × 4 = 84/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240 - Subtract the two like fractions:
84/240 - 126/240 = 84 - 126/240 = -42/240 - After reducing the fraction, the answer is -7/40
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