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. 3

B. 7

C. 17

D. 31

There are two examination rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is;

A. 20

B. 80

C. 100

D. 200

Rahim buys 3 kg mangoes for Rs 21 and sells them at 5 kg for Rs 50. To earn Rs 102 as profit, the mangoes to be sold by him should be

A. 34 kg

B. 52 kg

C. 26 kg

D. 32 kg

The average of 10 numbers is 40.2. Later it is found that two numbers have been wrongly copied. The first is 18 greater than the actual number and the second number added is 13 instead of 31. Find the correct average.

A. 40.1

B. 40.4

C. 40.6

D. 40.8.

E. None of the above

16 children are to be divided into two groups A and B of 10 and 6 children. The average percent marks obtained by the children of group A is 75 and the average percent marks of all the 16 children is 76. What is the average percent marks of children of groups B?

A. 77 1/3

B. 77 2/3

C. 78 1/3

D. 78 2/3

When a plot is sold for Rs. 18,700, the owner loses 15%. At what price must the plot be sold in order to gain 15% ?

A. Rs. 21, 000

B. Rs. 22,500

C. Rs. 25, 300

D. Rs. 25,800

The average number of printing error per page in a'bod 512 pages is 4. If the total number of printing error ml first 302 pages is 1,208, the average number of printinget per page in the remaining pages is'

A. 0

B. 4

C. 840

D. 90

E. None of the above

If he is able to sell only 1200 out of the 1500 watches he has made in the season, then in the season he has made a profit of:

A. Rs. 90,000

B. Rs. 75,000

C. Rs. 45,000

D. Rs. 60,000

Find the average of the following set of scores.746 1020 321 12 63 428 226 144

A. 367.5

B. 370

C. 360

D. 368.75

E. None of these

A pupil's marks were wrongly entered as 83 instead of 63. Due to that the average marks for the class got increased by half. The number of pupils in the class is:

A. 10

B. 20

C. 40

D. 73

E. None of the above

A trader marked the price of his commodity so as to include a profit of 25%. He allowed discount of 16% on the marked price. His actual profit was;

A. 5%

B. 9%

C. 16%

D. 25%

The average age of husband, wife and their child 3 years ago was 27 years and that of wife and the child 5 years ago was 20 years. What is the present age of the husband?

A. 40

B. 32

C. 28

D. 26

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. 35.2

B. 36.1

C. 36.5

D. 39.1

The average of six numbers is x and the average of three of these is y. If the average of the remaining three is z, then :

A. x = y + z

B. 2x = y + z

C. x = 2y + 2z

D. none of these

There are three classes X,Y and Z. Average of class X is 83. Average of Class Y is 76. Average of class Z is 85. Average of class X and Y is 79, average of class Y and Z is 81. Find average of three Classes

A. 81

B. 81.5

C. 82

D. 84

The average weight of 8 persons increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person?

A. 76 kg

B. 76.5 kg

C. 85 kg

D. Data inadequate

E. None of these

The average of five consecutive numbers is n. If the next two numbers are also included, the average will :

A. Remain the same

B. Increase by 1

C. Increase by 14

D. Increase by 2

Even after reducing the marked price of a transistor by Rs. 32, a shopkeeper makes a profit of 15%. If the cost price be Rs. 320, what percentage of profit would he have made if he had sold the transistor at the marked price?

A. 10%

B. 20%

C. 25%

D. None of these

E. None of these

A shopkeeper sold a T.V. set for Rs.17,940 with a discount of 8% and earned a profit of 19.6%. What would have been the percentage of profit earned if no discount was offered?

A. 24.8%

B. 25%

C. 26.4%

D. Cannot be determined

E. None of these

A grocer has a sale of Rs. 6435, Rs. 6927, Rs. 6855, Rs. 7230 and Rs. 6565 for 5 consecutive months. How much sale must he have in the sixth month so that he gets an average sale of Rs. 6500 ?

A. Rs. 4991

B. Rs. 5991

C. Rs. 6001

D. Rs. 6991

If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is:

A. 53.33

B. 54.68

C. 55

D. None of these

Marks obtained by Komal in English are equal to 1/3rd of marks obtained by her in Music. Total marks obtained by her in both the subjects is 160. How many marks did she secure in Music?

A. 120

B. 60

C. 30

D. 90

E. 100

Average cost of 5 apples and 4 mangoes is Rs. 36. The average cost of 7 apples and 8 mangoes is Rs. 48. Find the total cost of 24 apples and 24 mangoes.

A. 1044

B. 2088

C. 720

D. 324

A test has 50 questions. A student scores 1 mark for a correct answer, -1/3 for a wrong answer,and –1/6 for not attempting a question. If the net score of a student is 32, the number of questions answered wrongly by that student cannot be less than

A. 6

B. 12

C. 3

D. 9

By selling 75 toys a shopkeeper gains the selling price of 25 toys. Find his gain percent

A. 20%

B. 25%

C. 50%

D. 75%

Divide ?2379 into 3 parts so that their amounts after 2,3 and 4 years respectively may be equal, the rate of interest being 5% per annum at simple interest. The first part is

A. 759

B. 792

C. 818

D. 828

E. None of these

A trader buys a chair for Rs. 600 and sells it for Rs. 765 at a credit of 4 months. Reckoning money worth 6% p.a., his gain percent is:

A. 20%

B.

C. 25%

D.

Garima purchased a briefcase with an additional 10% discount on the reduced price after deducting 20% on the labeled price. If the labeled price was Rs. 1400, at what price did she purchase the briefcase?

A. Rs. 980

B. Rs. 1008

C. Rs. 1056

D. None of these

A banana costs Rs. 2.25 and an apple costs Rs. 3.00. What will be the total cost of 4 dozen of bananas and 3 dozen of apples?

A. Rs. 216

B. Rs. 108

C. Rs. 189

D. Rs. 225

E. Rs. 162