Bissoy.com
Doctors Medicines MCQs Q&A

In a series of 25 numbers, 25th number is twice the 23rd number and 24th number is fifteen more than 23rd number. Average of all the numbers is 49. The average of the first twelve numbers is 45 and the average of next 10 numbers is 53. If 23rd number, 24th number, and 25th number are p, q, and r respectively then which of the following is/are NOT correct? I. p + q + r = 155 II. p : q = 10 : 7 III. q : r = 5 : 7

In a series of 25 numbers, 25th number is twice the 23rd number and 24th number is fifteen more than 23rd number. Average of all the numbers is 49. The average of the first twelve numbers is 45 and the average of next 10 numbers is 53. If 23rd number, 24th number, and 25th number are p, q, and r respectively then which of the following is/are NOT correct? I. p + q + r = 155 II. p : q = 10 : 7 III. q : r = 5 : 7 Correct Answer Only II

Given:

Average of 25 numbers = 49

Average of the first 12 numbers = 45

Average of next 10 numbers = 53

r = 2p

q = p + 15

Formula Used:

Average = Sum of values/Number of values

Calculation:

Sum of the first 12 numbers/12 = 45

⇒ Sum of the first 12 numbers = 540

Sum of next 10 numbers/10 = 53

⇒ Sum of next 10 numbers = 530

Sum of all 25 numbers/25 = 49

⇒ Sum of all 25 numbers = 1125

⇒ 540 + 530 + p + q + r = 1125

⇒ 1070 + p + q + r = 1125

⇒ p + q + r = 155        ------(1)

⇒ p + p + 15 + 2p = 155

⇒ 4p = 140

⇒ p = 35

q = 35 + 15

⇒ q = 50

r = 2 × 35

⇒ r = 70

I. p + q + r = 155

From equation 1, I is correct

II. p : q = 10 : 7

35 : 50 = 7 : 10

⇒ II is not correct

III. q : r = 5 : 7

50 : 70 = 5 : 7

⇒ III is correct

∴ Only II is not correct.

Related Questions

The average of 24 numbers is 56. The average of the first 10 numbers is 71.7 and that of the next 11 number is 42. Then next three numbers (i.e 22nd, 23rd, and 24th) are in the ratio 1/2 : 1/3 : 5/12 What is the average of the 22nd and 24th numbers?
There are twelve numbers. The average of the first four numbers is 40.5 and the average of the last five numbers is 42.8. The sixth number is 0.2 less than the fifth number and 0.6 greater than the seventh number. If the average of the remaining twelve numbers is 43.2, then what is the average of the fifth and seventh numbers?
The average of fifteen numbers is 60. The average of the first seven numbers is 63 and the average of next five numbers is 59. The last number is half of the 13th number and the 14th number is four more than the last number. Which of the following is/are correct? I. Average of the last three numbers is an integer II. Fourteenth number is divisible by 11 III. Average of 13th and 15th number is not 65
The average of twelve numbers is 45.5. The average of the first four numbers is 41.5 and that of the next five numbers is 48. The 10th number is 4 more than the 11th number and 9 more than the 12th number. What is the average of the 10th and 12th numbers?
The average of twelve numbers is 58. The average of the first five numbers is 56 and the average of the next four numbers is 60. The 10th number is 4 more than the 11th number and the 11th number is one less than the 12th number. What is the average of the 10th and 12th numbers?
The average of twelve numbers is 55.5. The average of the first four numbers is 53.4 and that of the next four numbers is 54.6. The 10th number is greater than the 9th number by 3 but lesser than the 11th and 12th numbers by 2 and 3, respectively. What is the average of the 10th and the 12th numbers?
A series of terms would be in the order of increasing intension : (A) When each term in the series (except the first) connotes more attributes than the ones preceding it. (B) When each term in the series (except the first) is more specific than the one preceding (C) When each term in the series (except the first) connotes less attributes than the one preceding it. (D) When each term in the series (except the first) is less specific than the one preceding it. Choose the correct answer from the options given below:
Standing on a platform, Amit told Sunita that Aligarh was more than ten kilometres but less than fourteen kilometres from there. Sunita knew that it was more than twelve but less than fifteen kilometres from there. If both of them were correct, which of the following could be the distance of Aligarh from the platform?
The average of 12 number is 70. The average of the first four numbers is 60 while the average of the last five number is \(33\frac{1}{3}\%\) more than the average of the first four numbers. The 6th number is 20 more than the 5th number while the 7th number is 10 more than the 6th number. By what percent is the 6th number more than the 5th number?
The average of eight batsmen J, K, L, M, N, O, R, and T is compared. The number of batsman having average less than L are same as the number of batsman having average more than M. Average of T is less than M and more than K. Average of L is less than K. Average of two batsman lies between the average of M and L. Average of O is less than N and K both. Which of the following can be the correct sequence of their averages?