Subtract 21/42 from 40/20
1st number: 2 0/20, 2nd number: 21/42
40/20 - 21/42 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
40/20 = 40 × 21/20 × 21 = 840/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Subtract the two like fractions:
840/420 - 210/420 = 840 - 210/420 = 630/420 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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