Subtract 21/5 from 18/8
1st number: 2 2/8, 2nd number: 4 1/5
18/8 - 21/5 is -39/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 5 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 8 × 5 = 40,
18/8 = 18 × 5/8 × 5 = 90/40 - Likewise, for the 2nd fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Subtract the two like fractions:
90/40 - 168/40 = 90 - 168/40 = -78/40 - After reducing the fraction, the answer is -39/20
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