The mean of 100 item was 46. Later on, it was discovered that an item 16 was misread as 61 and another item 43 was misread as 34. It was also found that the number of items was 90 and not 100. Then what is the correct mean?
50
50.7
52
52
Average rainfall on Monday, Tuesday, Wednesday and Thursday is 420.5 cm and average on Tuesday, Wednesday, Thursday and Friday is 440.5 cm. If the ratio of rainfall for Monday and Friday is 20: 21, find the rainfall in cm on Monday and Friday.
1800, 1890
1600, 1680
1700, 1470
1700, 1470
The average of 5 consecutive integers starting with 'm' is n. What is the average of 6 consecutive integers starting with (m + 2)?
(n + 2)
(n + 3)
(n + 3)
5 members of a team are weighted consecutively and their average weight calculated after each member is weighed. If the average weight increases by one kg each time, how much heavier is the last player than the first one?
4 kg
20 kg
8 kg
8 kg
The average of two numbers A and B is 20, that of B and C is 19 and of C and A it is 21. What is the value of A?
24
22
20
20
A batsman in his 12th innings makes a score of 63 runs and thereby increases his average score by 2. The average of his score after 12th innings is
41
42
34
34
A.
41
Let he scores x runs before 12th innings.
Therefore,
⟹ 12 (x + 2) - 11x = 63
⟹ 12x + 24 - 11x = 63
⟹ x + 24 = 63
⟹ x = 39
Hence, his score after 12th innings shall be (39 + 2) = 41 runs.
In an examination average marks obtained by the girls of a class is 85 and the average marks obtained by the boys of the same class is 87. If the girls and boys are in the ratio 4 : 5, average marks of the whole class (approximately) is closest to
85.9
86.1
86.4
86.4
The average age of 30 students of a class is 14 years 4 months. After admission of 5 new students in the class the average becomes 13 years 9 months. The youngest one of the five new students is 9 years 11 months old. The average age of the remaining 4 new students is
11 years 2 months
13 years 6 months
12 years 4 months
12 years 4 months
Three Science classes A, B and C take a Life Science test. The average score of class A is 83. The average score of class B is 76. The average score of class C is 85. The average score of class A and B is 79 and C is 81. Then the average score of classes A, B and C is
81.5
81
80.5
80
Average of n numbers is a. The first number is increased by 2, second one is increased by 4, third one is increased by 8 and so on. The average of the new numbers is