The random variable X represents the number of defective items in a batch of 7, with the probability distribution given below:
x 0 1 2 3 4 5 6 7
P(X=x) 0.4 0.25 0.15 0.1 0.05 0.03 0.02 0.01
Find the probability that there is at least one defective item in the batch.
The probability is
.