Question
In an examination, the average marks obtained by the
students is 40. After correcting the quantitative mistakes, the average of 50 students is reduced to 30 from 40 and the overall average of the student is reduced to 35. Then find the total number of students who participated in that examination.Solution
Let the total number of students be x Average marks obtained by the students = 40 Total marks = 40x After correcting the quantitative mistakes the average decreased by (40-30) = 10 marks Total reduction = 10 × 50 = 500 Now According to the Question, (40x-500)/x = 35 35x = 40x-500 x= 100 Total number of students = 100
What is the standard deviation of a dataset if its variance is 17.64?
The digits of a two-digit number βNβ are reversed to form a new number βMβ. If M < N and N β M = 45, then which of the following maybe βNβ...
There are three numbers 'a', 'b' and 'c' (a < b < c) such that 'b' is equal to the average of 'a' and 'c'. 70% of 'c' is equal to 'a' and the difference...
If a number is decreased by 8 and divided by 12, the result is 16. What would be the result if 10 is subtracted from the number and then it is divided ...
Range of the given data 23,19,16,17,21,9,18,6.
The number of toy airplanes sold by shop B is 25% more than the number of toy helicopters sold by the same shop. If the ratio of number of toy gliders s...
A = (9/4) Γ B and C = (1/12) Γ A. If (A + B + C) = 300, then find the value of (12C β B).
In a village with a population of 1200, comprising both males and females, the ratio of males to females is 7:5. Each male receives 20 kg of rice, while...
Find the difference between minimum and maximum value of 'c' such that '5c4632' is always divisible by 3.
A, B and C hired a taxi for Rs. 880 and used it for 2, 4, 5 hours respectively. Hiring charges paid by B are: