How to solve the below question ? Which formula is required?

Question

The amount of hot chocolate to dispensed in the paper cups of a vending machine is normally distributed with a mean of 4.5 ounces and a standard deviation of 0.2 ounces what percent of all the paper cups will have more than 4.8 ounces of hot chocolate?

Answer 1

x = number of ounces

want to compute P(x > 4.8)

transform inequality to z-score = (x - mean)/SD

P(x > 4.8) = P(z > (4.8 - 4.5)/0.2 = P(z > 1.5) = P(z < -1.5) = 0.0688

convert probability to percentage by multiply probability by 100, so percentage = 6.88%