Subtract 63/21 from 90/20
1st number: 4 10/20, 2nd number: 3 0/21
90/20 - 63/21 is 3/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
63/21 = 63 × 20/21 × 20 = 1260/420 - Subtract the two like fractions:
1890/420 - 1260/420 = 1890 - 1260/420 = 630/420 - After reducing the fraction, the answer is 3/2
- In mixed form: 11/2
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