Answer:
20.41%
Step-by-step explanation:
87.95 - 70 = 17.95
17.95 / 87.95= 0.20409323479
0.20409323479 x 100 = 20.409323479
round it
= 20.41%
Answer:

Step-by-step explanation:
Given :In a recent questionnaire about food, a random sample of 970 adults were asked about whether they prefer eating fruits or vegetables, and 458 reported that they preferred eating vegetables.
To Find :What value of z should be used to calculate a confidence interval with a 95 % confidence level?
Solution:
Confidence level = 95 % i.e.0.95
So, significance level = 5% i.e. 0.05
So, the value of z corresponding to significance level 0.05 should be used to calculate a confidence interval with a 95 % confidence level
So, 
Hence z should be 1.645 to calculate a confidence interval with a 95 % confidence level.
Answer:
1. x=±4
2. t=±9
3. r=±10
4. x=±12
5. s=±5
Step-by-step explanation:
1. x^2 = 16
Taking square root on both sides

x=±4
2. t^2=81
Taking square root on both sides

t=±9
3. r^2-100=0

r=±10
4. x²-144=0
x²=144
Taking square root on both sides

x=±12
5. 2s²=50

s=±5 ..
Answer:

Step-by-step explanation:
Given



Required
Probability of selecting 2 orange marbles
The total number of marbles is:



The probability that the first selection is orange is:

Because it is a selection without replacement, the number of orange marbles and the total number of marbles would decrease by 1, respectively.
So, the probability that the selection is orange is:


The required probability is:




