Subtract 21/5 from 18/10
1st number: 1 8/10, 2nd number: 4 1/5
18/10 - 21/5 is -12/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 5 is 10
Next, find the equivalent fraction of both fractional numbers with denominator 10 - For the 1st fraction, since 10 × 1 = 10,
18/10 = 18 × 1/10 × 1 = 18/10 - Likewise, for the 2nd fraction, since 5 × 2 = 10,
21/5 = 21 × 2/5 × 2 = 42/10 - Subtract the two like fractions:
18/10 - 42/10 = 18 - 42/10 = -24/10 - After reducing the fraction, the answer is -12/5
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