Subtract 84/45 from 28/21
1st number: 1 7/21, 2nd number: 1 39/45
28/21 - 84/45 is -8/15.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
28/21 = 28 × 15/21 × 15 = 420/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
84/45 = 84 × 7/45 × 7 = 588/315 - Subtract the two like fractions:
420/315 - 588/315 = 420 - 588/315 = -168/315 - After reducing the fraction, the answer is -8/15
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