Average problems
- 1. A batsman in his 17th innings makes a score of 85 and their by increasing his average by 3. What is his average after the 17th innings ?
Options- A. 34
- B. 36
- C. 35
- D. 37 Discuss
Correct Answer: 37
Explanation:
16x + 85 = 17(x + 3)
x = 34 + 3 = 37
- 2. Five boxes of bananas sell for Rs. 30. how many boxes can you buy for Rs.9?
Options- A. 2
- B. 1.5
- C. 1.25
- D. 2.5 Discuss
Correct Answer: 1.5
Explanation:
Given Five boxes of bananas sell for Rs. 30.
=> 1 Box of Bananas for = 30/5 = Rs. 6
Then, for Rs. 9
=> 9/6 = 3/2 = 1.5
Hence, for Rs. 9, 1.5 box of bananas can buy.
- 3. Ian has 14 boxes of paper and divides them evenly between 4 coworkers. How many whole boxes did each coworker get?
Options- A. 2
- B. 2.5
- C. 3
- D. 3.5 Discuss
Correct Answer: 3
Explanation:
Given number of boxes = 14
Number of workers = 4
Now, number of whole boxes per worker = 14/4 = 3.5
Hence, number of whole boxes per each coworker = 3
- 4. The average price of 10 books is Rs. 12 while the average price of 8 of these books is Rs. 11.75. Of the remaining two books, if the price of one book is 60% more than the price of the other, what ia the pice of each of these two books ?
Options- A. 16,12
- B. 10,16
- C. 23,9
- D. 8,7 Discuss
Correct Answer: 10,16
Explanation:
Total pice of the two books = Rs. [(12 x 10) - (11.75 x 8)]
= Rs. (120 - 94) = Rs. 26.
let the price of one book be Rs. x
Then, the price of other book = Rs. (x + 60% of x) = Rs.(x+(3/5)x) = Rs. (8/5)x
So, x+(8/5)x =26 <=> x =10
The prices of the two books are Rs. 10 and Rs. 16
- 5. There are 100 students in 3 sections A, B and C of a class. The average marks of all the three sections was 84. The average of B and C was 87.5 and the average marks of students in A section was :
Options- A. 20
- B. 35
- C. 54
- D. 40 Discuss
Correct Answer: 20
Explanation:
Numbers of students in section A = x
? Numbers of students in section B and C = (100 ? x)
? x 70 + (100 ? x) 87.5 = 84 100
=> 70x + 87.5 100 ? 87.5x = 8400
=> 8750 ? 17.5x = 8400
=> 17.5x = 8750 ? 8400 => x = 20.
- 6. Third proportion of 10 and 20 is
Options- A. 30
- B. 40
- C. 25
- D. 20 Discuss
Correct Answer: 40
Explanation:
The third proportional of two numbers p and q is defined to be that number r such that
p : q = q : r.
Here, required third proportional of 10 & 20, and let it be 'a'
=> 10 : 20 = 20 : a
10a = 20 x 20
=> a = 40
Hence, third proportional of 10 & 20 is 40.
- 7. Navaneet has thrice the money Poonam has and Poonam has 25% more money than Hebah. If the average money of the three is Rs. 350, What is the amount that Navaneet has ?
Options- A. Rs. 175
- B. Rs. 220.75
- C. Rs. 218.55
- D. Rs. 656.25 Discuss
Correct Answer: Rs. 656.25
Explanation:
Assume Hebah has Rs. M
Since 25% more money at Poonam
=> Money at Poonam = M + (25% of M)
=> Money at Poonam = M + 0.25M = Rs. 1.25M
Money with Navaneet is thrice the money with Poonam,
=> Money at Navaneet = 3(1.25M) = Rs. 3.75M
Now, sum of all Money = (M + 1.25M + 3.75M) = Rs. 6M
But given the average of the money is Rs. 350
=> 6M/3 = 350
=> 2M = 350
=> M = 350/2 = Rs. 175
=> Amount of money Navaneet has = Rs. 3.75M = 3.75 x 175 = Rs. 656.25.
- 8. 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 ?
Options- A. 97
- B. 98
- C. 92
- D. 93 Discuss
Correct Answer: 97
Explanation:
Marks in English = 85×7 ? 83×6
= 595 ? 498
= 97
- 9. Find the average of first 50 natural numbers?
Options- A. 25
- B. 25.5
- C. 26
- D. 26.5 Discuss
Correct Answer: 25.5
Explanation:
We Know that sum of the n natural numbers =
Then sum of 50 natural numbers= = 1250
Average of the 50 natural numbers = = 25.5
- 10. The average of five numbers is 27. If one number is excluded, the average becomes 25. The excluded number is :
Options- A. 25
- B. 35
- C. 45
- D. 55 Discuss
Correct Answer: 35
Explanation:
Excluded number = (27 x 5) - (25 x 4) = 135 - 100 = 35.
More in Aptitude:
Programming
Copyright ©CuriousTab. All rights reserved.