Subtract 20/4 from 81/2
1st number: 40 1/2, 2nd number: 5 0/4
81/2 - 20/4 is 71/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 4 is 4
Next, find the equivalent fraction of both fractional numbers with denominator 4 - For the 1st fraction, since 2 × 2 = 4,
81/2 = 81 × 2/2 × 2 = 162/4 - Likewise, for the 2nd fraction, since 4 × 1 = 4,
20/4 = 20 × 1/4 × 1 = 20/4 - Subtract the two like fractions:
162/4 - 20/4 = 162 - 20/4 = 142/4 - After reducing the fraction, the answer is 71/2
- In mixed form: 351/2
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