Subtract 40/9 from 21/80
1st number: 21/80, 2nd number: 4 4/9
21/80 - 40/9 is -3011/720.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 9 × 80 = 720,
40/9 = 40 × 80/9 × 80 = 3200/720 - Subtract the two like fractions:
189/720 - 3200/720 = 189 - 3200/720 = -3011/720
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