Subtract 90/4 from 28/21
1st number: 1 7/21, 2nd number: 22 2/4
28/21 - 90/4 is -127/6.
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,
28/21 = 28 × 4/21 × 4 = 112/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
90/4 = 90 × 21/4 × 21 = 1890/84 - Subtract the two like fractions:
112/84 - 1890/84 = 112 - 1890/84 = -1778/84 - After reducing the fraction, the answer is -127/6
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