A large store has a customer service department where customers can go to ask for help with store-related issues. According to store records, approximately \(\dfrac{1}{4}\) of all customers who go to the service department ask for help finding an item. Assuming the reason each customer goes to the service department is independent from customer to customer. Based on the approximation, what is the probability that at least 1 of the next 4 customers who go to the service department will ask for help finding an item?

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The probability that at least 1 of the next 4 customers goes can be found by adding the probability that 1 goes, 2 goes, 3 goes, and 4 goes. Another option is to find the probability that no one goes, and subtract that from one.

The probability that a given person does not go is \(1-\dfrac{1}{4}\). So the probability that 4 people don't go is:

$$ \left(\frac{3}{4}\right)^4 $$

Subtract that from 1:

$$ 1-\left(\dfrac{3}{4}\right)^4 $$