math
posted by Kath .
The average number of calories in a 1.5 ounce chocolate bar is 225. Suppose that the distribution of calories is approximately normal with standard deviation =10. Find the probability that a randomly selected chocolate bar will have
a) Between 200 and 220 calories
b) Less than 200 calories

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The average number of calories in a 1.5 ounce chocolate bar is 225. Suppose that the distribution of calories is approximately normal with standard deviation =10. Find the probability that a randomly selected chocolate bar will have
a) Between 200 and 220 calories
b) Less than 200 calories