Add 81/90 and 20/28
81/90 + 20/28 is 113/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 28 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 28 × 45 = 1260,
20/28 = 20 × 45/28 × 45 = 900/1260 - Add the two like fractions:
1134/1260 + 900/1260 = 1134 + 900/1260 = 2034/1260 - 2034/1260 simplified gives 113/70
- So, 81/90 + 20/28 = 113/70
In mixed form: 143/70
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