Answer to Question #49745 in Statistics and Probability for Sarah

Question

After the quizzes are marked, you’re told that the scores on the exam were distributed normally (μ=50, σ=10). You are also told that students with scores in the top 10% will receive a chocolate bar, and students with scores in the top 25% will receive a stick of gum.
a) What is the minimum score needed to receive a chocolate bar?
b)Would a score of 57 earn a stick of gum?

I don't know the steps, so confused!