Subtract 90/5 from 81/4
1st number: 20 1/4, 2nd number: 18 0/5
81/4 - 90/5 is 9/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 5 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 4 × 5 = 20,
81/4 = 81 × 5/4 × 5 = 405/20 - Likewise, for the 2nd fraction, since 5 × 4 = 20,
90/5 = 90 × 4/5 × 4 = 360/20 - Subtract the two like fractions:
405/20 - 360/20 = 405 - 360/20 = 45/20 - After reducing the fraction, the answer is 9/4
- In mixed form: 21/4
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