The probability of snow for each of the next three days is $\frac{2}{3}$. What is the probability that it will snow at least once during tho

Case 1: once: 2/3 * 1/3 * 1/3 * 3

Case 2: twice: 2/3 * 2/3 * 1/3 * 3 C 2

case 3: 3 times: (2/3)^3

2/27*3 + 4/27*3 + 8/27 = 6/27 + 12/27 + 8/27 = 26/27.

We could use Complementary Counting for this.

The probability that it will not slow at all is      \(\frac{1}{3} \times \frac{1}{3} \times \frac{1}{3} = \frac{1}{27}\)        

Then we minus the total by   \(\frac{1}{27}\) 

\(1 - \frac{1}{27} = \frac{26}{27}\)