Subtract 21/45 from 7/80
7/80 - 21/45 is -91/240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
7/80 = 7 × 9/80 × 9 = 63/720 - Likewise, for the 2nd fraction, since 45 × 16 = 720,
21/45 = 21 × 16/45 × 16 = 336/720 - Subtract the two like fractions:
63/720 - 336/720 = 63 - 336/720 = -273/720 - After reducing the fraction, the answer is -91/240
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