Statistics and Average

If the arithmetic mean of sevety five numbers is calculated, it is 35. If each number is increased by 5, then mean of new numbers is:

• ক. 30
• খ. 40
• গ. 70
• ঘ. 90

If 3a +5b = 10 and 5a + 3b = 30, what is the average (arithmetic mean) of a and b?

• ক. 4
• খ. 2.5
• গ. 3.5
• ঘ. 4.5

The average of Selim’s marks in 7 subjects is 75. His average in six subjects excluding Science is 72. How many marks did he get in Science?

• ক. 72
• খ. 90
• গ. 93
• ঘ. 98

A motorist travels to a place 150 km away at an average speed of 50 km and returns at 30 km per hour. What is his average speed for the whole journey in km per hour?

• ক. 35
• খ. 37
• গ. 37.5
• ঘ. 40

If a mark of 76 or higher represents A grade, what is the nearest percentage of students who receive an A?

• ক. 14%
• খ. 17%
• গ. 20%
• ঘ. 9%

If p is less than q , which of the following is the greater than p and less than q?

• ক. (q – p)/2
• খ. pq/2
• গ. (p + q)/2
• ঘ. pq

Average weight of 8 persons is 120 lb. One person leaves the group and a new person comes in and the new average is 122 lb. If the weight of the outgoing person is 110 lb, then what is the weight of the incoming person?

• ক. 126
• খ. 122
• গ. 118
• ঘ. 120

Karim, Rahim, Ram & Shyam have the following probabilities of passing the admission test 20%, 30%, 25% and 50% respectively. What is the probability of Karim, Rahim and Shyam will pass the test?

• ক. 30%
• খ. 3%
• গ. 0%
• ঘ. 100%

A school had 100 students aged 20years on an average. At the of the year 20 students aged 22 years on an average left and 25 students of 18 years on an average joined the school. What is the average age of the present students of the school?

• ক. 20.1
• খ. 18
• গ. 20
• ঘ. 22

Rahim average 70 in his first m number of exams. After taking n more exams he had an overall average of 75. In terms of m and n his average for the last n exams was—

• ক. 5n/m + 75
• খ. (70m + 75n)/(m + n)
• গ. 80
• ঘ. (5m + 75)/n

Average of P numbers is x and average of N numbers is y. Find the average of all of the numbers.

• ক. (Px + Ny)/(p + N)
• খ. (Px + Ny)/xy(P + N)
• গ. x + y
• ঘ. (x + y)/(P + N)

Francis had an average of 75 on her first four Geometry test. After taking the next test her average dropped to 72. How much did she get in fifth test?

• ক. 58
• খ. 60
• গ. 73.5
• ঘ. 54

The average of three numbers is V. If one of the numbers is Z and another is Y, then what is the remaining number?

• ক. z/x - z - y
• খ. 3V - Z - Y
• গ. V - Z - Y
• ঘ. ZY - V

The average of 6, 8 and 10 equals the average of 7, 9 and --

• ক. 8
• খ. 9
• গ. 11
• ঘ. 1

In a group of four people the height of the group members are 5 feet 4 inches, 5 feet, 5 feet 6 inches and 4 feet 10 inches. The average height of the group members is:

• ক. 5 feet
• খ. 5 feet 1 inches
• গ. 5 feet 2 inches
• ঘ. 5 feet 3 inches

If the average of 16, 20 and n is between 18 and 21 inclusive, what is the greatest possible value of n?

• ক. 18
• খ. 21
• গ. 27
• ঘ. 54

If Taka 4500 was invested in bonds of acorporation when the price per bond was Tk.9.00 and Taka 3000 was invested in bonds of another corporation when the price was Tk.10.00 per bond, What was the average price of bonds purchased?

• ক. Tk.9.625
• খ. Tk.9.50
• গ. Tk.9.40
• ঘ. Tk.9.375

The average of 7 numbers of 40. If 3 more numbers with an average of 21 are added to these numbers,what will be the average of the combined 10 numbers?

• ক. 6.1
• খ. 30.1
• গ. 30.3
• ঘ. 34.3

The average of 6 number is 8.5, when one number is discarded the average of the remaining numbers becomes 7.2. What is the discarded number?

• ক. 7.8
• খ. 9.8
• গ. 10
• ঘ. 12.4

The cost of making x units is Y = 5x + 10, the average cost of making 10 units is--

• ক. Tk. 5
• খ. Tk.6
• গ. Tk.7
• ঘ. Tk.8

The sun of daily income of P, Q and R is Tk.90. If Q earns taka 10 more than P and R earns double of what Q earns, then what is the average of daily income of P and Q?

• ক. 40 Tk.
• খ. 30 Tk.
• গ. 20 Tk.
• ঘ. 10 Tk.

On Monday a person mailed 8 packages weighting an average of 99/8 pounds and on Tuesday 4 packages weighting an average of 61/4 pounds. What was the average weight on pounds of all the packages the person mailed on both days?

• ক. 111/4
• খ. 40/13
• গ. 27/13
• ঘ. 109/4

There are 8 job applicants sitting in waiting room; 4 women and 4 men. If two of the applicants are selected at random, what is the probability that both will be women?

• ক. 1/2
• খ. 3/7
• গ. 1/4
• ঘ. 3/14

The average of 10 numbers is -10. If the sum of 6 of them is 100, then what is the average of the other 4 numbers?

• ক. -100
• খ. -50
• গ. 50
• ঘ. 100

If a3 - b3 = 513 and a - b = 3, then ab =?

• ক. 54
• খ. 55
• গ. 45
• ঘ. 34

The average of three numbers is 7. If 2 of the numbers are zero, then what if the 3rd number?

• ক. 15
• খ. 17
• গ. 19
• ঘ. 21

Average of the five consecutive even number is 8. Which is the smallest of the 5 numbers?

• ক. 4
• খ. 3
• গ. 5
• ঘ. 6

The average of 20, 70 and x is 40. If the average of 20, 70, x and y is 50, then y =?

• ক. 100
• খ. 80
• গ. 70
• ঘ. 60

Sum of P and Q is 72 and the value of R is 42. What is the average of P, Q and R?

• ক. 32
• খ. 34
• গ. 36
• ঘ. 38

Salma's average in four tests is 80%. What mark does she need score in her fifth test to make her average 84%?

• ক. 100%
• খ. 94%
• গ. 84%
• ঘ. 96%

What is the average of 0.36, 4.6, 0.64 and 2.4?

• ক. 1
• খ. 2
• গ. 2.5
• ঘ. 10

If the sum of (3, 7 and x) is 18, then the average of (3, 7 and x) is--

• ক. 6
• খ. 7
• গ. 8
• ঘ. 9

If 6 and x have the same mean as 2, 4 and 24, what is the value of x?

• ক. 5
• খ. 10
• গ. 14
• ঘ. 36

The average of 6 numbers is 25. If 3 more numbers with an average of 22 are added to these numbers, what will be the average of the combined 9 numbers?

• ক. 20
• খ. 22
• গ. 24
• ঘ. 25

If Tk.45000 was invested in the share market when the price per share was Tk.90 and Tk.30000 was invested when the price per share was Tk.100, what was the average price per share purchesd?

• ক. Tk.96.25
• খ. Tk.95.00
• গ. Tk.94.00
• ঘ. Tk.93.75

Razia spent 3 hours climbing 6 miles up a hill. She spent 2 hours coming down the hill on a different path which had a length of 8 miles. For Razia's completed climb up and down the hill, what was her average speed in miles per hour?

• ক. 2.0
• খ. 2.5
• গ. 2.8
• ঘ. 3.0

A car travles 180 km from A to B at 60 kilometers/hour and returns from B to A along the same route at 90 kilometers/hour. The average speed in kilometers per hour for the round trip is:

• ক. 72
• খ. 36
• গ. 180
• ঘ. 30

A train passes city X at 8.25 am and city Y at 11.05 am. The distance between city X and Y is 320 miles. What is the average speed in miles per hour of the train?

• ক. 135
• খ. 120
• গ. 270
• ঘ. None of these

The average weight for a group of 20 women is 130 pounds. If the average weight for 75% of these women was 140 pounds, what was the average weight in pounds for the rest of the women?

• ক. 100
• খ. 110
• গ. 120
• ঘ. 135

Jamil's average score in 4 tests was 80 out of a possible 100. If his scores in 2 of the tests were 65 and 70, what is the lowest that either of his other scores could have been?

• ক. 70
• খ. 80
• গ. 90
• ঘ. 85

In company X, the average salary of 10 of the employees is Tk.30000, the average salary of 30 other employees is Tk.40000 and the average salary of the remaining 20 employees Tk.60000. What is the average salary of the 60 employees at the company?

• ক. Tk.40000
• খ. Tk.43000
• গ. Tk.45000
• ঘ. Tk.60000

The average age of 40 employees in abranch of a bank is 35 years. When a new employee joined the bank the average age increased to 35.5 years. What is the age of the new employee?

• ক. 55.5
• খ. 50
• গ. 50.5
• ঘ. 20.5

If the sum of (8, 5 and x) is 21, then the average of (8, 5 and x) is--

• ক. 7
• খ. 9
• গ. 2
• ঘ. 3.5

In a class of 22 students, 21 students get an average of 44 marks. If the remaining students get 66 marks, the average marks of the whole class is--

• ক. 30
• খ. 45
• গ. 15
• ঘ. None of these

The average of a, b, c is 6 and a - b = 4, ab = 21, what is the value of c?

• ক. 6
• খ. 7
• গ. 8
• ঘ. 9

The average temperature on Wednesday,Thursday and Friday was 25°c. The average temperature on Thursday, Friday and Saturday was 24°c. If the temperature on saterday was 27°c, what was the temperature on Wednesday?

• ক. 24°c
• খ. 21°c
• গ. 27°c
• ঘ. 30°c

When a student weighting 45 kgs left a class, the average weight of the remaining 59 students increased by 200g. What is the average weight of the remaining 59 students?

• ক. 57 kgs
• খ. 56.8 kgs
• গ. 58.2 kgs
• ঘ. 52.2 kgs

The of 5 quantities is 6. The average of 3 of them is 8. What is the average of the remaining two numbers?

• ক. 6.5
• খ. 4
• গ. 3
• ঘ. 3.5

What is the maximum number of half-pint bottles of cream that can be filled with a 4-gallon can of cream? (2 pt. = 1 qt. and 4 qt. = 1 gal)

• ক. 16
• খ. 24
• গ. 30
• ঘ. 64

The average of 5 numbers is 40. If 2 more numbers with an average of 21 are added to these numbers, what will be the average of the combined numbers?

• ক. 8.7
• খ. 30.1
• গ. 30.3
• ঘ. 34.6

The addition of 10 digits is 462. The average of their first four digits is 52 and the average of last 5 digits is 38. What is the fifth digit?

• ক. 64
• খ. 60
• গ. 50
• ঘ. 62

If the average of four numbers k, 2k + 3, 3k - 5, and 5k + 1 is 63. What is the value of k?

• ক. 11
• খ. 15.75
• গ. 22
• ঘ. 23

The average mark obtained by 15 students was 10 and the average mark obtained by 10 students was 15. What was the average mark obtained by all students?

• ক. 10
• খ. 8
• গ. 12
• ঘ. 15

If 8x + 8y = 64, what is the average of x and y?

• ক. 16
• খ. 4
• গ. 0
• ঘ. 1