Question

The following measurements were recorded for the duration, in seconds, of phone calls in a call-center of a major corporation:

30        32        27        20

32        30        26        30

33 29

1. the mode of the dataset is:

1. 26 s                  b)   27 s           c)   30 s           d)   32 s           e)    33 s

2. The median of the dataset is:

1. 30.15 s             b)   28.9 s        c)   30 s           d)   28.9 s²       e)   30 s²

3. The mean of the duration of the phone call is:

1. 30.15 s²           b)   28.9 s        c)   30.15 s      d)   30 s           e)    28.9 s²

4. The variance of the dataset is:

1. 28.9 s               b)   14.54 s      c)   3.81 s        d)   14.54 s²     e)   3.81 s²

5. The third quartile of the dataset is:

1. 20 s                  b)   27 s           c)   30 s           d)   32 s           e)   33 s

6. the 20% trimmed mean is:

1. 28.67 s             b)   29.67 s     c)   28.5 s        d)   29.5 d        e)   30 s

The two events A and B are independent. Hence:

7. The relation P[A] = P[A|B] necessarily applies.

1. True                b)   False

8. The relation P[B] = P[B|A] necessarily applies.

1. True                b)   False

9. The relation P[A∩B] = P[A]P[B] necessarily applies.

1. True                b)   False

10. The relation P[A∩B] = Ø necessarily applies.

1. True                b)   False

11. If A and B are also mutually exclusive, then the relation P[A∩B] = Ø necessarily applies.

1. True                b)   False

12. If A and B are also mutually exclusive, then P[A U B] =P[A] + P[B] necessarily applies.

1. True                b)   False

Answer 1