Quiz Discussion

The average sale of car dealership was 15 cars per week. After a promotional scheme the average sale increased to 21 cars per week. The percentage increased in the sale of cars was-

• 1]

  39.33%

• 2]

  40%

• 3]

  \(42\frac{6}{7}\)%

• 4]

  140%

The average age of students of a class is 15.8 years. The average age of boys in the class is 16.4 years and that of the girls is 15.4 years. The ratio of the number of boys to the number of girls in the class is-

• 1] 1 : 2
• 2] 2 : 3
• 3] 3 : 4
• 4] 3 : 5

The average income of A, B and C is Rs. 12,000 per month and average income of B, C and D is Rs. 15,000 per month. If the average salary of D be twice that of A, then the average salary of B and C is in Rs. :

• 1] 8,000
• 2] 18,000
• 3] 13,500
• 4] 9,000

The average of the ages of Sumit, Krishna and Rishabh is 43 and the average of the ages of Sumit, Rishabh and Rohit is 49. If Rohit is 54 years old, what is Krishna’s age?

• 1] 24 years
• 2] 36 years
• 3] 45 years
• 4] Cannot be determined
• 5] None of these

The mean weight of 100 students in a class is 46 kg. The mean weight of boys is 50 and of girls is 40 kg. Therefore, the number of boys is:

• 1] 50
• 2] 60
• 3] 70
• 4] 65

Out of 9 persons, 8 persons spent Rs. 30 on each of their meals. The ninth one spends Rs. 20 more than the average expenditure of all the nine. The total money spent by all of them was

• 1]

  Rs 260

• 2]

  Rs 290

• 3]

  Rs 292.5

• 4]

  Rs 400.5

The average of five numbers is 306.4. The average of the first two numbers is 431 and the average of the last two numbers is 214.5. What is the third number?

• 1] 52
• 2] 108
• 3] 321
• 4] Cannot be determined
• 5] None of these

The frequency distribution data is given below. If the average age is 17 years, the value of m is

• 1] 1
• 2] 2
• 3] 3
• 4] 4

The average age of a family with 5 members is 28. If one of the 5 members of age 20 is excluded the average age of the family becomes -

• 1] 25
• 2] 20
• 3] 30
• 4] 24

The average age of P, Q and R is 15 years more than R's age. If the total age of P and Q together is 39 years, then R's age is ?

• 1] 12 years
• 2] 24 years
• 3] 16 years
• 4] 14 years