Subtract 21/12 from 18/80
1st number: 18/80, 2nd number: 1 9/12
18/80 - 21/12 is -61/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
18/80 = 18 × 3/80 × 3 = 54/240 - Likewise, for the 2nd fraction, since 12 × 20 = 240,
21/12 = 21 × 20/12 × 20 = 420/240 - Subtract the two like fractions:
54/240 - 420/240 = 54 - 420/240 = -366/240 - After reducing the fraction, the answer is -61/40
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