The probability of a certain brand of battery going dead within 15 hours is 1/3. Noah has a toy that requires 4 of these batteries. He wants to simulate the situation to estimate the probability that at least one battery will die before 15 hours are up. b. After doing the simulation 5 times, Noah has the following results.
What should he use as an estimate of the probability that at least one battery will die within 15 hours? (Write your answer as a fraction, decimal, or percent.)