Subtract 21/9 from 20/40
1st number: 20/40, 2nd number: 2 3/9
20/40 - 21/9 is -11/6.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 9 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
20/40 = 20 × 9/40 × 9 = 180/360 - Likewise, for the 2nd fraction, since 9 × 40 = 360,
21/9 = 21 × 40/9 × 40 = 840/360 - Subtract the two like fractions:
180/360 - 840/360 = 180 - 840/360 = -660/360 - After reducing the fraction, the answer is -11/6
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