Subtract 3/84 from 90/21
1st number: 4 6/21, 2nd number: 3/84
90/21 - 3/84 is 17/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
3/84 = 3 × 1/84 × 1 = 3/84 - Subtract the two like fractions:
360/84 - 3/84 = 360 - 3/84 = 357/84 - After reducing the fraction, the answer is 17/4
- In mixed form: 41/4
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