Subtract 21/30 from 30/80
30/80 - 21/30 is -13/40.
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,
30/80 = 30 × 3/80 × 3 = 90/240 - Likewise, for the 2nd fraction, since 30 × 8 = 240,
21/30 = 21 × 8/30 × 8 = 168/240 - Subtract the two like fractions:
90/240 - 168/240 = 90 - 168/240 = -78/240 - After reducing the fraction, the answer is -13/40
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