Subtract 20/21 from 7/2
1st number: 3 1/2, 2nd number: 20/21
7/2 - 20/21 is 107/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 2 × 21 = 42,
7/2 = 7 × 21/2 × 21 = 147/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
20/21 = 20 × 2/21 × 2 = 40/42 - Subtract the two like fractions:
147/42 - 40/42 = 147 - 40/42 = 107/42 - In mixed form: 223/42
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