Quiz Discussion

The average monthly salary of 12 workers and 3 managers in a factory was Rs. 600. When one of the manager whose salary was Rs. 720, was replaced with a new manager, then the average salary of the team went down to 580. What is the salary of the new manager?

• 1] 640
• 2] 690
• 3] 420
• 4] 570

In a primary school the average weight of male students is 65.9 kg and the average weight of female students is 57 kg. If the average weight of all the students ( both male and female ) is 60.3 kg and the number of male students in the school is 66, what is the number of female students in the school?

• 1] 162
• 2] 168
• 3] 180
• 4] 112

Mean of 10 numbers is 30. Later on it was observed that numbers 15, 23 are wrongly taken as 51, 32. The correct mean is :

• 1] 25.5
• 2] 32
• 3] 30
• 4] 34.5

The average of marks in Mathematics for 5 students was found to do 50. Later, it was discovered that in the case of one student the marks 48 were misread as 84. The correct average is :

• 1] 40.2
• 2] 40.8
• 3] 42.8
• 4] 48.2

The arithmetic mean of the scores of a group of students in a test was 52. The brightest 20% of them secured a mean score of 80 and the dullest 25% a mean score of 31. The mean score of remaining 55% is-

• 1] 45
• 2] 50
• 3] 51.4 approx
• 4] 54.6 approx

There are two sections A and B of a class, consisting of 36 and 44 students' respectively. If the average weight of section A is 40kg and that of section B is 35kg, find the average weight of the whole class.

• 1] 30 kg
• 2] 35 kg
• 3] 42.5 kg
• 4] 37.25 kg

The average of 6 observations is 45.5. If one new observation is added to the previous observations, then the new average becomes 47. The new observation is :

• 1] 58
• 2] 56
• 3] 50
• 4] 46

The average of six number is x and the average of three of these is y. the average of the remaining three is z, then 

• 1]

  x=y+z

• 2]

  2x=y+z

• 3]

  x=2y+2z

• 4]

  x=2yz

The average of four consecutive even numbers is 15. The 2nd highest number is :

• 1] 12
• 2] 18
• 3] 14
• 4] 16

The average age of group of 20 girls is 15 years and that of another group of 25 boys it is 24 years. The average age of the two groups mixed together is :

• 1] 19.5 yearas
• 2] 20 years
• 3] 21 yearas
• 4] 21.5 years