Add 81/90 and 20/84
81/90 + 20/84 is 239/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 90 × 14 = 1260,
81/90 = 81 × 14/90 × 14 = 1134/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
20/84 = 20 × 15/84 × 15 = 300/1260 - Add the two like fractions:
1134/1260 + 300/1260 = 1134 + 300/1260 = 1434/1260 - 1434/1260 simplified gives 239/210
- So, 81/90 + 20/84 = 239/210
In mixed form: 129/210
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