Subtract 18/30 from 21/80
21/80 - 18/30 is -27/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 30 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
21/80 = 21 × 3/80 × 3 = 63/240 - Likewise, for the 2nd fraction, since 30 × 8 = 240,
18/30 = 18 × 8/30 × 8 = 144/240 - Subtract the two like fractions:
63/240 - 144/240 = 63 - 144/240 = -81/240 - After reducing the fraction, the answer is -27/80
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