Subtract 9/5 from 21/20
1st number: 1 1/20, 2nd number: 1 4/5
21/20 - 9/5 is -3/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 5 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Likewise, for the 2nd fraction, since 5 × 4 = 20,
9/5 = 9 × 4/5 × 4 = 36/20 - Subtract the two like fractions:
21/20 - 36/20 = 21 - 36/20 = -15/20 - After reducing the fraction, the answer is -3/4
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