Subtract 18/20 from 21/4
1st number: 5 1/4, 2nd number: 18/20
21/4 - 18/20 is 87/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
21/4 = 21 × 5/4 × 5 = 105/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
18/20 = 18 × 1/20 × 1 = 18/20 - Subtract the two like fractions:
105/20 - 18/20 = 105 - 18/20 = 87/20 - In mixed form: 47/20
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