can you find the answers of the questions (find the answers of the questions in next post)

1. Calculate the sample standard deviation using the following data:

        X 

        4

        5

        2

        6

        4

        3

        4

The standard deviation is which of the following?

A. 10

B. 1.66

C. 1.20

D. 1

2. Using the standardized normal table supplied with this exam determine what Z value would be used to set up a confidence interval at the 99 percent confidence level.

A. .01

B. 1.01

C. 1.65

D. 2.57

3. Using the standardized normal table supplied with this exam determine what Z value would be used to set up a confidence interval at the 95 percent confidence level.

A. .05

B. 1.05

C. 1.65

D. 1.96

 Find the answers

1. If for two variable x and y, the covariance. Variance of x and variance of y are 40, 16 and 256 respectively, what is the value of the correlation coefficient?

(a) 0.01    (b) 0.625    (c)   0.4   (d)  0.5

 
2. Following are the two normal equations obtained for deriving the regression line of y and x :

5a + 10b = 40; 10a + 25b = 95 the regression line of y on x is given by

(a) 2x + 3y = 5

(b) 2y + 3x = 5

(c) y = 2 + 3x

(d) y = 3 + 5x

3. If the regression line of y on x and of x on y are given by 2x+3y = —1 and 5x + 6y = —1 then the arithmetic means of x and y are given by

(a) (1, —1)   (b) (-1, 1)  (c)  (-1, —1)  (d) (2. 3)

4. Given the following equations: 2x — 3y = 10 and 3x + 4y = 15, which one is the regression equation of x on y?

(a) 1st equation (b) 2nd equation (c) both the equations (d) none

Find the answers 

1. The probability of getting heads in both trials, when a balanced coin is tossed twice will be

(a)   1/4

(b)  1/2

(c)  1

(d)   3/4

2. Two cards are drawn at random from a pack of 52 cards. The probability of these two being aces is

(a) 1/26 

(b)  1/221

(c)  1/2

(d)  None of these

3. The probability that a leap year selected at random contains 53 Sundays is

(a) 7/366                   (b) 26/183                   (c) 1/7                          (d) 2/7

4. The probability of getting more than 7 when pair of dice is thrown is:

          (a) 7/36                     (b) 7/12                       (c) 5/12                           (d) None of these

5. The probability of having at least one head in 3 throws with a coin is:

          (a) 7/8                                (b) 318                        (c) 1/8                            (d) None of these

6. If A and B are independent events, then P (A ) equals.

        (a) P (A) + P (B)        (b) P (A) P (B)      (c) P (A/B)       (d) P (B/A)

7.If A and B are mutually exclusive events. Then P (A ) equals.

(a) 0                         (b)    2                         (c) 1                                (d) none of these

8. A bag contains 2 red, 3 green and 2 blue balls. Two balls are drawn at random. What is the        probability that none of the balls drawn is blue?

(a) 10/21 (b) 11/21 (c) 2/7 (d) 5/7

9.A bag contains 4 white, 5 red and 6 blue balls. Three balls are drawn at random from the bag.    The probability that all of them are red is:

(a) 2/91 (b)1/22 (c) 3/22 (d) 2/77