Subtract 90/18 from 21/5
1st number: 4 1/5, 2nd number: 5 0/18
21/5 - 90/18 is -4/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 5 × 18 = 90,
21/5 = 21 × 18/5 × 18 = 378/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
90/18 = 90 × 5/18 × 5 = 450/90 - Subtract the two like fractions:
378/90 - 450/90 = 378 - 450/90 = -72/90 - After reducing the fraction, the answer is -4/5
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