5×s+8×n=5549
s+n=850
n=850-s
5×s+8(850-s)=5549
5×s+6800-8×s=5549
-3×s=-1251
s=417
417 student tickets were sold
To find the slope, you divide the difference of the y-coordinates of 2 points on a line by the difference of the x-coordinates of those same 2 points .
Answer:
im not fully sure because im a 4th grader but 52 i think.
Mean = (19 + 20 + 21 + 22 + 23)/5 = 105/5 = 21
x x - mean (x - mean)^2
19 -2 4
20 -1 1
21 0 0
22 1 1
23 2 4
Sum = 10
Standard deviation = sqrt(sum(x - mean)^2 /n) = sqrt(10/5) = sqrt(2)