A survey in a study skills class asked the 20 students enrolled in the class how many hours (rounded to the nearest hour) they had spent studying on the previous evening. The 20 responses are summarized by the histogram below.

To the nearest tenth of an hour, what is the average number of hours for the 20 survey responses?

A survey in a study skills class asked the 20 students enrolled in the class how many hours (rounded to the nearest hour) they had spent studying on the previous evening. The 20 responses are summarized by the histogram below. What fraction of the students responded that they had spent less than 3 hours studing?

A survey in a study skills class asked the 20 students enrolled in the class how many hours (rounded to the nearest hour) they had spent studying on the previous evening. The 20 responses are summarized by the histogram below. The teacher decides to show the data in a circle graph (pie chart). What should be the measure of the central angle of the sector for 3 hours?

A salesperson recorded her sales during a particular 5-day work week, shown in the table above, in order to study her daily sales. During her eight-hour shift on Wednesday, the salesperson sold items that had an average price of $8.10. To the nearest tenth of an item, what is the number of items she sold per hour on Wednesday?

The Harrisburg Recreation Center recently changed its hours to open 1 hour later and close 3 hours later than it had previously. Residents of Harrisburg age 16 or older were given a survey and 560 residents replied. The survey asked each resident his or her student status (high school, college, or nonstudent) and what he or she thought about the change in hour (approve, disapprove, or no opinion). The results are summarized in the table below. What fraction of these nonstudent resisdents replied they disapproved of the change in hours?

The Harrisburg Recreation Center recently changed its hours to open 1 hour later and close 3 hours later than it had previously. Residents of Harrisburg age 16 or older were given a survey and 560 residents replied. The survey asked each resident his or her student status (high school, college, or nonstudent) and what he or she thought about the change in hour (approve, disapprove, or no opinion). The results are summarized in the table below. Suppose a person will be chosen at random from these 560 residents. Which of the following values is closest to the probability that the person chosen will NOT be a high student and will NOT have replied with no opinion?

There are 20 students in a Chemistry class and 30 students in a Physics class. Find the number of students which are either in Physics class or Chemistry class in the following case : the classes meet at the same hour.

There are 20 students in a Chemsitry class and 30 students in a Physics class. .Find the number of students which are either in physics class or chemistry class in the following cases (i)Two classes meet at the same hour.