Subtract 63/80 from 21/30
21/30 - 63/80 is -7/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 30 × 8 = 240,
21/30 = 21 × 8/30 × 8 = 168/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
63/80 = 63 × 3/80 × 3 = 189/240 - Subtract the two like fractions:
168/240 - 189/240 = 168 - 189/240 = -21/240 - After reducing the fraction, the answer is -7/80
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