Subtract 18/10 from 21/15
1st number: 1 6/15, 2nd number: 1 8/10
21/15 - 18/10 is -2/5.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 10 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 15 × 2 = 30,
21/15 = 21 × 2/15 × 2 = 42/30 - Likewise, for the 2nd fraction, since 10 × 3 = 30,
18/10 = 18 × 3/10 × 3 = 54/30 - Subtract the two like fractions:
42/30 - 54/30 = 42 - 54/30 = -12/30 - After reducing the fraction, the answer is -2/5
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