Statistics and Average

26. 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

27. 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

28. 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

29. 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

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

• ক. 54
• খ. 55
• গ. 45
• ঘ. 34

31. 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

32. 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

33. 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

34. 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.

35. 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

36. 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

37. 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

38. 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

39. 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

40. 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

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

• ক. 8
• খ. 9
• গ. 11
• ঘ. 1

42. 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

43. 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

44. 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)

45. 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

46. 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

47. 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%

48. 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

49. 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

50. 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%