The reading levels of a random sample of elementary students are represented by the dot plot. Which decimal is the best approximation of the mean reading level for this group of students?
Select one:

2.7

1.5

2.3

1.9

For what values of x is x2 + 2x = 24 true?

What is the value of x in the equation 2(x-4) = 4(2x + 1)?

At the olympic games, many events have several rounds of competition. one of these events is the men's 100-meter backstroke. the upper dot plot shows the times (in seconds) of the top 8 finishers in the final round of the 2012 olympics. the lower dot plot shows the times of the same 8 swimmers, but in the semifinal round. which pieces of information can be gathered from these dot plots? (remember that lower swim times are faster.) choose all answers that apply: a: the swimmers had faster times on average in the final round. b: the times in the final round vary noticeably more than the times in the semifinal round. c: none of the above.