question_answer

The following table gives the ages of teachers in XYZ school.

Age (in years)     Number of teachers
20-25	70
25-30	110
30-35	165
35-40	320
40-45	200
45-50	135

A teacher is selected at random from the group, then which of the following statements is INCORRECT?

A)  Probability of a teacher having age greater than or equal to 35, is\[\frac{131}{200}.\].

B)  Probability of at eacher having age more than or equal to 25 and less than 40, is\[\frac{119}{200}.\]

C)  Probability of a teacher selected is of age not less than 30, is \[\frac{17}{200}.\]

D)  Probability of a teacher selected from the youngest group, is \[\frac{14}{200}.\]

Correct Answer: C

Solution :

Total number of teacher = 70 + 11 +165 + 320 + 200 + 135 = 1000 (a) Number of teachers having the age greater than or equal to 35 are (320 + 200 +135) = 655 Required probability (b) Number of teacher having age more than or equal to 25 and less than 40 = 110 + 165 + 320 + = 595 Required probability (c) Number of teachers of age not less than 30 = 165 + 320 + 200 + 135 = 820 Required probability (d) Numbers of teachers in the youngest group i.e.,  Required probability