Subtract 21/5 from 18/4
1st number: 4 2/4, 2nd number: 4 1/5
18/4 - 21/5 is 3/10.
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,
18/4 = 18 × 5/4 × 5 = 90/20 - Likewise, for the 2nd fraction, since 5 × 4 = 20,
21/5 = 21 × 4/5 × 4 = 84/20 - Subtract the two like fractions:
90/20 - 84/20 = 90 - 84/20 = 6/20 - After reducing the fraction, the answer is 3/10
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