FACTS  AND  FORMULAE  FOR  AVERAGE QUESTIONS

 

 

1. Average =Sum of observationsNo. of observations

2. Suppose a man covers a certain distance x kmph and an equal distance at y kmph. Then, the average speed during the whole journey is2xyx+yKmph

Q:

20 men went to a restaurant. Ninteen of them paid Rs.70 each and the twentieth man paid Rs.90.25 more than the average of all the 20 men. What is the total bill ?

A) Rs. 1495 B) Rs. 548
C) Rs. 850 D) Rs. 1750
 
Answer & Explanation Answer: A) Rs. 1495

Explanation:

Let the average bill paid by twenty members = 'x'

But 19 men paid each = Rs. 70

20th man paid Rs. 90.25 more than the avg bill of 20 = x + 90.25

20x = 19(70) + x + 90.25
19x = 1330 + 90.25
19x = 1420.25
x = 1420.25/19 = Rs. 74.75

But the total bill = 20 x 74.75 = Rs. 1495.

Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Bank Clerk , Bank PO

10 7646
Q:

The average monthly salary of 24 employees in an organisation is Rs. 1500. If the manager's salary is added, then the average salary increases by Rs. 400. What is the manager's monthly salary ?

A) Rs. 8840 B) Rs. 11,500
C) Rs. 12,800 D) Rs. 9450
 
Answer & Explanation Answer: B) Rs. 11,500

Explanation:

Manager's monthly salary

= Rs. (1900 x 25 - 1500 x 24) = Rs. 11,500

Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: AIEEE , Bank Exams , CAT , GATE
Job Role: Bank Clerk , Bank PO

11 7456
Q:

Given below are the ages in yrs of a group of children. What is the medium age?

 

7, 9, 8, 6 , 5, 3, 9, 2



A) 6.5 B) 5
C) 6.125 D) 6
 
Answer & Explanation Answer: A) 6.5

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: Bank Exams

1 7368
Q:

The median of the numbers 3, 1, 1 5, 2 and 7 is

 

A) 3.5 B) 2.5
C) 2 D) 3
 
Answer & Explanation Answer: B) 2.5

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: Bank Exams

1 7338
Q:

The average marks of a student in 7 subjects is 85. His average marks in 6 subjects except English is 83. What is his marks in English ?

A) 97 B) 98
C) 92 D) 93
 
Answer & Explanation Answer: A) 97

Explanation:

Marks in English  = 85×7 – 83×6

= 595 – 498

= 97

Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Bank Clerk , Bank PO

22 7311
Q:

It costs Rs. p each to send the first thousand messsages and Rs. q to send each subsequent one . If r is greater than 1,000, how many Rupees will it cost to send r messages ?

A) 1000 (r - p) + pq B) 1000 p + qr
C) 1000 (r - q) + pr D) 1000(p - q) + qr
 
Answer & Explanation Answer: D) 1000(p - q) + qr

Explanation:

We need to find the total cost to send r messsages, r > 1000.

The first 1000 messsages will cost Rs.p each (Or) 

The total cost of first 1000 messsages = Rs.1000p

The remaining (r - 1000) messsages will cost Rs.q each (Or)

The cost of the (r - 1000) = Rs.(r - 1000)y

 

Therefore, total cost = 1000p + rq - 1000q

= 1000(p - q) + qr

Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: GATE , CAT , Bank Exams , AIEEE
Job Role: Bank PO , Bank Clerk

15 7270
Q:

19 friends went to a restaurant for a combined weekend dinner party. 13 of them spent Rs. 79 each on their dinner and the rest spent Rs. 4 more than the average expenditure of all the 19. What was the total money spent by them?   

A) Rs. 1398.96 B) Rs. 1457.09
C) Rs. 1662.35 D) Rs. 1536.07
 
Answer & Explanation Answer: D) Rs. 1536.07

Explanation:

Let average expenditure was Rs. R

13 x 79 + 6x(R + 4) = 19R

=> R = Rs. 80.84

Total money = 19 x 80.84 = Rs. 1536.07.

Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: AIEEE , Bank Exams , CAT , GATE
Job Role: Bank Clerk , Bank PO

29 6948
Q:

In a cinema hall for the matinee show which started at 2.30 pm and ended at 5.30 pm the vehicle parking lot had only three wheelers (auto rickshaws) and four wheelers. Today the wheels of the vehicles parked was counted and found to be 240. What could be the number of three wheelers parked therein ?

A) 48 B) 41
C) 45 D) 43
 
Answer & Explanation Answer: A) 48

Explanation:

3X + 4y = 240
by substitute through options 48 is correct

Report Error

View Answer Report Error Discuss

Filed Under: Average
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Bank Clerk

5 6931