Subtract 21/20 from 90/5
1st number: 18 0/5, 2nd number: 1 1/20
90/5 - 21/20 is 339/20.
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,
90/5 = 90 × 4/5 × 4 = 360/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
21/20 = 21 × 1/20 × 1 = 21/20 - Subtract the two like fractions:
360/20 - 21/20 = 360 - 21/20 = 339/20 - In mixed form: 1619/20
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