Add 21/84 and 15/90
21/84 + 15/90 is 5/12.
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,
21/84 = 21 × 15/84 × 15 = 315/1260 - Likewise, for the 2nd fraction, since 90 × 14 = 1260,
15/90 = 15 × 14/90 × 14 = 210/1260 - Add the two like fractions:
315/1260 + 210/1260 = 315 + 210/1260 = 525/1260 - 525/1260 simplified gives 5/12
- So, 21/84 + 15/90 = 5/12
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