Subtract 90/5 from 21/4
1st number: 5 1/4, 2nd number: 18 0/5
21/4 - 90/5 is -51/4.
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,
21/4 = 21 × 5/4 × 5 = 105/20 - Likewise, for the 2nd fraction, since 5 × 4 = 20,
90/5 = 90 × 4/5 × 4 = 360/20 - Subtract the two like fractions:
105/20 - 360/20 = 105 - 360/20 = -255/20 - After reducing the fraction, the answer is -51/4
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