Subtract 9/20 from 21/5
1st number: 4 1/5, 2nd number: 9/20
21/5 - 9/20 is 15/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 5 × 4 = 20,
21/5 = 21 × 4/5 × 4 = 84/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
9/20 = 9 × 1/20 × 1 = 9/20 - Subtract the two like fractions:
84/20 - 9/20 = 84 - 9/20 = 75/20 - After reducing the fraction, the answer is 15/4
- In mixed form: 33/4
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