Subtract 9/4 from 90/21
1st number: 4 6/21, 2nd number: 2 1/4
90/21 - 9/4 is 57/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 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 4 × 21 = 84,
9/4 = 9 × 21/4 × 21 = 189/84 - Subtract the two like fractions:
360/84 - 189/84 = 360 - 189/84 = 171/84 - After reducing the fraction, the answer is 57/28
- In mixed form: 21/28
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