Question

When Sophia runs the 400 meter dash, her finishing times are normally distributed with a mean of 75 seconds and a standard deviation of 1.1 second. What probability of races will her finishing time be between 74.2 and 76.4 seconds?
Round to the hundredths place (2 places after the decimal)

Answer 1

Answer: 90% of the time.

Step-by-step explanation: This is because you can add the two different times and the standard time of 75 seconds, divide it all by 3 leaving you with 75.2 and that is 0.2 away from the original between those times all together. Take that 0.2 and subtract it from the 1.1 deviation and you’ll get 0.9 times that by 100 and you get it in a percentage; 90%.