200? I’m sorry I’m not that good at math
Tan(12) = 40/d
d = 40/tan(12)
d = 188.19m
The stem and leaf plot will look like:
6 | 1 5 8 - 3 scores
7 | 1 7 7 9 - 4 scores
8 | 2 3 4 5 7 9 - 6 scores
9 | 0 1 4 7 9 - 1 score
To total up the number of students who scored less than 90, we have 3 under 60-69, 4 under 70-79, and 6 under 80-89, so this is 3 + 4 + 6. This is the third choice.
Alright, so let's make a function for the number of seats in a row. Number of seats = 25+ (number of row-1)(2) because it goes up by two. We start with 25, so we have that, then we get that it adds by 2 every row. However, for the first row it only has 25, so we have the number of the row -1 .If we figure out the 200th row, we get 25+398=423. Adding that and 25, we get 448. 448*100=44800, and we get that number because with an even number of rows, we add the 1st and 200th, the 2nd and 99th, and so on. This works because as you go up rows, you add two, and as you decrease rows, you decrease by two, so they cancel each other out and form 100 pairs. All pairs are equal.
I think 5 may be the common factor for 35 and 60.