Please help! The ratio of boys to girls at King Middle School is 3 : 2. What is the ratio of girls to all students?

A. 3 : 2

B: 2 : 3

C: 3 : 5

D: 2 : 5

The sum of two numbers is 86, and their difference is 20. find the two numbers

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.

Prove sin2a + cos2a - 1 / sin2a + cos2a + 1 = 1 - tana / 1 + cota