The probability of drawing an 'a' or 'c' at least once in 6 draws is approximately 0.98.
The probability of drawing an 'a' or 'c' at least once in 6 draws can be calculated by considering the complementary probability—finding the probability of not drawing 'a' or 'c' in any of the draws and then subtracting it from 1.
There are a total of 26 letters in the basket. The probability of not drawing 'a' in a single draw is 25/26, and the probability of not drawing 'c' is also 25/26. Since the draws are independent and with replacement, the probability of not drawing 'a' or 'c' in a single draw is (25/26)^2.
To find the probability of not drawing 'a' or 'c' in all 6 draws, we raise this probability to the power of 6: (25/26)^6. Then, we subtract this probability from 1 to get the probability of drawing 'a' or 'c' at least once:
1−(25/26)^6.
Calculating this expression gives approximately 0.98, so the probability of drawing 'a' or 'c' at least once in 6 draws is approximately 0.98 when rounded to two decimal places.