Calculate the circumference of the two semi circles, which equals a full circle. Then add the two sides of the track.
Circumference is pi x diameter = 3.14 x 22.8 = 71.592, so, you would need to add 71.592 + 49.2 + 49.2 = 169.992 meters, and that would be the length of one lap of the track.
X is 90 degrees. If AB is the diameter, then it passes through the centre. X is 90 degrees because the angle in a semicircle is always a right angle.
Answer:
a) 320 students
b) 25 students
Step-by-step explanation:
Number of 18-years old in the survey:
(We add all frequency points for each line)
0 + 30 + 20 + 60 + 70 + 40 + 60 + 40 + 0 = 320 students
Number of 18 year old spending between 25 and 35 minutes: 40 + 65 = 105
Number of 12 year old spending between 25 and 35 minutes: 30 + 50 = 80
105 - 80 = 25 students
