Subtract 18/4 from 21/10
1st number: 2 1/10, 2nd number: 4 2/4
21/10 - 18/4 is -12/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 4 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 10 × 2 = 20,
21/10 = 21 × 2/10 × 2 = 42/20 - Likewise, for the 2nd fraction, since 4 × 5 = 20,
18/4 = 18 × 5/4 × 5 = 90/20 - Subtract the two like fractions:
42/20 - 90/20 = 42 - 90/20 = -48/20 - After reducing the fraction, the answer is -12/5
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