The scores on the exam public health professionals take to be certified follows a normal distribution with a mean score of 75 points and a standard deviation of 7 points. What is the probability someone scores 78.5 or less on the exam? Round your answer to 4 decimal places.

Plz explain. Ty

Randy took a standardized test that is normally distributed. He scored a 105 on the test. The nationwide mean score on the test was 94 and the standard deviation was 6.2. What percent of the tested population scored higher than Randy on the test? Round to the nearest whole percent. O 2% 4% 96% O 94% 11%

Can someone please help? Thank you.

Ap Stats

Find the area of the shaded region. The graph to the right depicts IQ scores of​ adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15.   Click to view page 1 of the table. LOADING... Click to view page 2 of the table. LOADING...                       85 110         A graph with a bell-shaped curve, divided into 3 regions by 2 lines from top to bottom, one on the left side and one on the right side. The region between the lines is shaded. Moving from left to right, the x-axis below the first line is labeled 85. The x-axis below the second line is labeled 110.       Question content area bottom Part 1 The area of the shaded region is enter your response here. ​(Round to four decimal places as​ needed.)

Juan and his family are relocating to Los Angeles. They purchased a home they really like, which cost $739,000 . The mean home price in the area is $ 735,000 with a standard deviation $17,050 . Find the z-score of the price of Juan's home relative to the prices among all the homes in the area. Round your answer to two decimal places. z=

Scores on a test have a mean of 66 and a standard diviation of 9. Michelle has a score of 57. Convert Michelles score to z-score.

The prices of all college textbooks follow a bell-shaped distribution with a mean of $108 and a standard deviation of $21. What percentage of the price that is more than 140? Show your works and read the table.

We have provided simple data sets for you to practice the basics of finding measures of variation. For each data set, determine the a. range. b. sample standard deviation. 4, 2, 0, 2, 2