Add 28/84 and 72/90
28/84 + 72/90 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 90 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
28/84 = 28 × 15/84 × 15 = 420/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
72/90 = 72 × 14/90 × 14 = 1008/1260 - Add the two like fractions:
420/1260 + 1008/1260 = 420 + 1008/1260 = 1428/1260 - 1428/1260 simplified gives 17/15
- So, 28/84 + 72/90 = 17/15
In mixed form: 12/15
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