Question

A well-known college entrance exam has scores that are normally distributed with a mean of 500 and a standard deviation of 100. What percentage of test-takers will score 450 or higher? a) 30.85% b) 69.15% c) 19.15% d) 0.50%

Answer 1

To find the percentage of test-takers who will score 450 or higher on the college entrance exam, you need to standardize the score and calculate the proportion using a standard normal distribution table or calculator.

Step-by-step explanation:

To calculate the percentage of test-takers who will score 450 or higher on the college entrance exam, we need to find the area under the normal distribution curve to the right of 450. First, we need to standardize the score using the formula z = (x - mean) / standard deviation. Plugging in the values, we get z = (450 - 500) / 100 = -0.5. We can then use a standard normal distribution table or a calculator to find the proportion of test-takers who scored less than -0.5, which is equivalent to the proportion who scored 450 or higher. The answer is approximately 0.6915, which can be expressed as 69.15% (option b).