Quiz Discussion

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 average age of an adult class is 40 years. 12 new students with an average age of 32 years join the class, thereby decreasing the average by 4 years. The original strength of the class was-

• 1] 10
• 2] 11
• 3] 12
• 4] 15

The mean of 100 items was 46. Later on it was discovered that an item 16 was misread as 61 and another item 43 was misread as 34. It was also found that the number of item was 90 and not 100. Then what is the correct mean ?

• 1] 50
• 2] 50.7
• 3] 52
• 4] 52.7

The average weight of A, B and C is 40 kgs. Weight of C is 24 kgs more than A’s weight and 3 kgs less than B’s weight. What will be the average weight of A, B, C and D, if D weights 15 kgs less than C?

• 1] 42 kgs
• 2] 40 kgs
• 3] 36 kgs
• 4] 38 kgs

A set A consists of integers 27, 28, 30 and 33. If integer k is included in the set, the average of set A will increase by 30%. What is the value of integer k ?

• 1] 68
• 2] 79
• 3] 73.75
• 4] 75.25

The average (arithmetic mean) of 330, 360 and 390 is :

• 1]

  \({3^{27}} + {3^{57}} + {3^{87}}\)

• 2]

  \({3^{29}} + {3^{59}} + {3^{89}}\)

• 3]

  \({3^{60}}\)

• 4]

  \({3^{177}}\)

The average age of 40 students of class is 18 years. When 20 new students are admitted to the same class, the average age of the students of the class is increased by 6 months. The average age of newly admitted students is ?

• 1] 19 years
• 2] 19 years 6 months
• 3] 20 years
• 4] 20 years 6 months

The average pocket money of 3 friend A, B, C is Rs. 80 in a particular month. If B spends double and C spends triple of what A spends during that month and if the average of their unspent pocket money is Rs. 60, then A spends (in Rs.)-

• 1] Rs. 10
• 2] Rs. 20
• 3] Rs. 30
• 4] Rs. 40

A library has an average of 510 visitors on Sundays and 240 on other days. The average number of visitors per day in a month of 30 days beginning with a Sunday is

• 1]

  285

• 2]

  276

• 3]

  280

• 4]

  290

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