h Search

Q:

The average of five consecutive odd numbers is 61. What is the difference between the highest and lowest numbers :

A) 4	B) 8
C) 12	D) 16

Answer & Explanation Answer: B) 8

Explanation:

Let the numbers be x, x + 2, x + 4, x + 6 and x + 8.

Then [x + (x + 2) + (x + 4) + (x + 6) + (x + 8) ] / 5 = 61.

or 5x + 20 = 305 or x = 57.

So, required difference = (57 + 8) - 57 = 8

Report Error

View Answer Report Error Discuss

Filed Under: Average

Q:

Out of 9 persons, 8 persons spent Rs. 30 each for their meals. The ninth one spent Rs. 20 more than the average expenditure of all the nine. The total money spent by all of them was :

A) Rs. 292.50	B) Rs. 297.50
C) Rs. 298	D) Rs. 298.50

Answer & Explanation Answer: A) Rs. 292.50

Explanation:

Let the average expenditure be Rs. x Then,

9x=[(8*30)+(x+20)]<=>9x =x+260 <=> x =32.50

Total money spent = 9x = Rs. (9 x 32.5O) = Rs 292. 50

Report Error

View Answer Report Error Discuss

Filed Under: Average

Q:

1.Ravens are black.Ravens are evil.All evil are black

2.Horses are faster than eagles.All eagles are hawks.Horses are faster than hawks

3.No priest is a saint.Peter is a priest.Peter is a saint.

A) 1 only	B) 2 and 3
C) 3 only	D) 3 and 4

Answer & Explanation Answer: D) 3 and 4

Explanation:

Report Error

View Answer Report Error Discuss

Filed Under: Verbal Reasoning - Logical Deduction

Q:

A team of 8 persons joins in a shooting competition. The best marksman scored 85 points. If he had scored 92 points, the average score for the team would have been 84. The number of points, the team scored was :

A) 665	B) 657
C) 658	D) 678

Answer & Explanation Answer: A) 665

Explanation:

Let the total score be x.

(x + 92 - 85) / 8 = 84.

So, x + 7 = 672 => x = 665.

Report Error

View Answer Report Error Discuss

Filed Under: Average

Q:

The mean of 50 observations was 36. It was found later that an observation 48 was wrongly taken as 23. The corrected new mean is :

A) 35	B) 36.5
C) 40	D) 42

Answer & Explanation Answer: B) 36.5

Explanation:

Correct Sum = (36 * 50 + 48 - 23) = 1825.

Correct mean = = 1825/50 = 36.5

Report Error

View Answer Report Error Discuss

Filed Under: Average

Q:

If the mean of a, b, c is M and ab + bc + ca = 0, then the mean of $\frac{a^{2} + b^{2} + c^{2}}{3}$ is :

A) M	B) 3 M^2
C) 2 (M/3)	D) M^2

Answer & Explanation Answer: B) 3 M^2

Explanation:

We have : ( a + b + c) / 3 = M or (a + b + c) = 3M.

Now. ${(a + b + c)}^{2} = {(3 M)}^{2} = 9 M^{2}$ .

$< = > a^{2} + b^{2} + c^{2} + 2 (a b + b c + c a) = 9 M^{2}$

$a^{2} + b^{2} + c^{2} = 9 M^{2}, (a b + b c + c a = 0)$

Required mean = $(\frac{a^{2} + b^{2} + c^{2}}{3}) = \frac{9 M^{2}}{3} = 3 M^{2}$ .

Report Error

View Answer Report Error Discuss

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

Q:

A student was asked to find the arithmetic mean of the numbers 3, 11, 7, 9, 15, 13, 8, 19, 17, 21, 14 and x. He found the mean to be 12. What should be the number in place of x ?

A) 6	B) 7
C) 8	D) 9

Answer & Explanation Answer: B) 7

Explanation:

Clearly, we have (3 + 11 + 7 + 9 + 15 + 13 + 8 + 19 + 17 + 21 + 14 + x) / 12 = 12.

or 137 + x = 144 or x = 144 - 137 = 7.

Report Error

View Answer Report Error Discuss

Filed Under: Average

Q:

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 ?

A) 16,12	B) 10,16
C) 23,9	D) 8,7

Answer & Explanation Answer: B) 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

Report Error

View Answer Report Error Discuss

Filed Under: Average

Searching for "h"

Quick Links