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