To find out approximately how many minutes students in a high school are spending texting while in class, the guidance counselor
conducts a carefully designed and implemented random survey. The table below shows the number of minutes per week these randomly selected students text in class. Minutes Per Week Students Text in Class
What is the estimated number of minutes per week all students in this school, the population mean, text while in class based on the sample, rounded to the nearest tenth of a minute?
Well, from the first row to the second you added +7 on both sides. On the other rows you merely did some arithmetic. Usually one gets from the first line to the last one directly :)
The new girth is 22 inches; the reference girth is 20 inches. The weight is proportional to the girth, so the reference weight will get multiplied by 22/20 = 11/10.
