Answer:
a) 1
1
+
1
b)1
3
+
1
8
Step-by-step explanation:
Hey i would answer but you didn’t provide enough context! make sure to upload images with your question hun.
To find the unit rate, divide the numerator and denominator of the given rate by the denominator of the given rate. So in this case, divide the numerator and denominator of 70/5 by 5, to get 14/1, or 14 students per class, which is the unit rate. <— that’s your answer! :)
Answer: a) 683 b) 1067
Step-by-step explanation:
The confidence interval for population proportion is given by :-

a) Given : Significance level :
Critical value : 
Margin of error : 
Formula to calculate the sample size needed for interval estimate of population proportion :-

Hence, the required sample size would be 683 .
b) If no estimate of the sample proportion is available then the formula to calculate sample size will be :-

Hence, the required sample size would be 1067 .
Part 1:
Given that the length of the chord is 18 cm and the chord is midway the radius of the circle.
Thus, half the angle formed by the chord at the centre of the circle is given by:

Now,

Therefore, the radius of the circle is
10.4 cm to 1 d.p.
Part 2I:
Given that the radius of the circle is 10 cm and the length of chord AB is 8 cm. Thus, half the length of the chord is 4cm. Let the distance of the mid-point O to /AB/ be x and half the angle formed by the chord at the centre of the circle be θ, then

Now,

Part 2II:
Given that the radius of the circle is 10cm and the angle distended is 80 degrees. Let half the length of chord CD be y, then:

Thus, the length of chord CD = 2(6.428) = 12.856 which is approximately
12.9 cm.