1
NDA 2019 Paper 1
MCQ (Single Correct Answer)
+2.5
-0.83
The mean of 100 observations is 50 and the standard deviation is 10. If 5 is subtracted from each observation and then it is divided by 4, then what will be the new mean and the new standard deviation respectively?
A
45, 5
B
11.25, 1.25
C
11.25, 2.5
D
12.5, 2.5
2
NDA Mathematics 1st September 2024
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
Let x - 3y + 4 = 0 and 2x - 7y + 8 = 0 be two lines of regression computed from some bivariate data. If byx and bxy are regression coefficients of lines of regression of y on x and x on y respectively, then what is the value of bxy + 7byx?
1
-2
2
1
3
2
4
5
3
NDA Mathematics 1st September 2024
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
What is the mean deviation of the first 10 natural numbers?
1
2
2
2.5
3
3
4
3.5
4
NDA Mathematics 1st September 2024
MCQ (Single Correct Answer)
+2.5
-0.833
Change Language
Let $\rm \Sigma_{i=1}^9x_i^2=885$ If M is the mean and σ is the standard deviation of  x1, x2, x3.....x9 then what is the value of M2 + σ2?
1
100
2
95
3
90
4
85
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