Subtract 21/8 from 15/10
1st number: 1 5/10, 2nd number: 2 5/8
15/10 - 21/8 is -9/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 10 × 4 = 40,
15/10 = 15 × 4/10 × 4 = 60/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
21/8 = 21 × 5/8 × 5 = 105/40 - Subtract the two like fractions:
60/40 - 105/40 = 60 - 105/40 = -45/40 - After reducing the fraction, the answer is -9/8
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