I really need help with this problem can someone please explain how to solve it? I already know the answer is 75 bags I just don't know how to get that answer.

Betty's Bite-Size Candies are packaged in bags. The number of candies per bag is normally distributed, with mean of 50 candies and a standard deviation of 3. At a quality control checkpoint, a sample of bags is checked, and 12 bags contain fewer that 47 candies. How many bags were probably taken as samples.

Question

I really need help with this problem can someone please explain how to solve it? I already know the answer is 75 bags I just don't know how to get that answer.

Betty's Bite-Size Candies are packaged in bags. The number of candies per bag is normally distributed, with mean of 50 candies and a standard deviation of 3. At a quality control checkpoint, a sample of bags is checked, and 12 bags contain fewer that 47 candies. How many bags were probably taken as samples.