Add 81/84 and 20/45
81/84 + 20/45 is 355/252.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 84 × 15 = 1260,
81/84 = 81 × 15/84 × 15 = 1215/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
20/45 = 20 × 28/45 × 28 = 560/1260 - Add the two like fractions:
1215/1260 + 560/1260 = 1215 + 560/1260 = 1775/1260 - 1775/1260 simplified gives 355/252
- So, 81/84 + 20/45 = 355/252
In mixed form: 1103/252
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