Step 1 :The problem is asking for the probability of getting 3 or more successes (getting a popcorn coupon) in 10 trials (buying movie tickets), given the probability of success on each trial is 0.608. This is a binomial probability problem. We can solve it by summing up the probabilities of getting exactly 3, 4, 5, ..., 10 successes.
Step 2 :Let's denote the probability of success (getting a popcorn coupon) as p, which is 0.608, and the number of trials (buying movie tickets) as n, which is 10.
Step 3 :By calculating, we get the probability as 0.9893105888489067.
Step 4 :Rounding to three decimal places, the final answer is 0.989.
Step 5 :So, the probability that 3 or more of the tickets have popcorn coupons is \(\boxed{0.989}\).