Quiz Discussion

If the arithmetic mean of 7, 5, 13, x and 9 is 10, then the value of x is :

• 1] 10
• 2] 12
• 3] 14
• 4] 16

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 weight of 8 men is increased by 1.5 kg when one of the men, who weight 65 kg is replaced by a new man. The weight of the new man is-

• 1] 70 kg
• 2] 74 kg
• 3] 76 kg
• 4] 77 kg

Out of four numbers the average of the first three is 16 and that of the last three is 15. If the last number is 20, than first number is :

• 1] 25
• 2] 21
• 3] 23
• 4] 28

Five years ago, the average age of A, B, C and D was 45 yr. with E joining them now, the average of all the five is 49 yr. How old is E?

• 1] 25 years
• 2] 40 years
• 3] 45 years
• 4] 64 years

A shop of electronic goods is closed on Monday. The average daily sales for remaining six days of a week is Rs. 15,640 and the average sale of Tuesday to Saturday is Rs. 14,124. The sales on Sunday is -

• 1] Rs. 20,188
• 2] Data inadequate
• 3] Rs. 23,220
• 4] Rs. 21,704

The average temperature for the first four days of a week is 40.2° C and that of the last four days is 41.3° C. If the average temperature for the whole 40.6°C, then the temperature on the fourth day is-

• 1] 40.8° C
• 2] 41.3° C
• 3] 41.8° C
• 4] 38.5° C

The average weight of 3 men, A, B and C is 84 kg. Another man D joins the group and the average now becomes 80 kg. If another man E whose weight is 3 kg more than that of D, replaces A then the average weight of B, C, D and E becomes 79 kg. What is the weight of A ?

• 1] 70 kg
• 2] 72 kg
• 3] 75 kg
• 4] 80 kg

Nine persons went to a hotel for taking their meals. Eight of them spent Rs. 12 each on their meals and the ninth spent Rs. 8 more than the average expenditure of all the nine. What was the total money spent by them.

• 1] Rs. 115
• 2] Rs. 116
• 3] Rs. 117
• 4] Rs. 118

a, b, c, d, e, f, g are consecutive even numbers. j, k, l, m, n are consecutive odd numbers. The average of all the numbers is :

• 1]

  \(3\left( {\frac{{a + n}}{2}} \right)\)

• 2]

  \(\left( {\frac{{1 + d}}{2}} \right)\)

• 3]

  \(\left( {\frac{{a + b + m + n}}{4}} \right)\)

• 4]

  \(3\left( {\frac{{j + c + n +g}}{4}} \right)\)