Subtract 21/16 from 18/40
1st number: 18/40, 2nd number: 1 5/16
18/40 - 21/16 is -69/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 16 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 40 × 2 = 80,
18/40 = 18 × 2/40 × 2 = 36/80 - Likewise, for the 2nd fraction, since 16 × 5 = 80,
21/16 = 21 × 5/16 × 5 = 105/80 - Subtract the two like fractions:
36/80 - 105/80 = 36 - 105/80 = -69/80
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