1
NDA 2019 Paper 1
MCQ (Single Correct Answer)
+2.5
-0.83
If all the natural numbers between 1 and 20 are multiplied by 3, then what is the variance on the resulting series?
A
99.75
B
199.75
C
299.25
D
399.25
2
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
3
NDA Mathematics 21 April 2024
MCQ (Single Correct Answer)
+2.5
-0.83
Change Language

From data (-4, 1), (-1, 2), (2, 7) and (3, 1), the regression line of y on x is obtained as $y = a + bx$, then what is the value of $2a + 15b$?

A

6

B

11

C

17

D

21

4
NDA Mathematics 21 April 2024
MCQ (Single Correct Answer)
+2.5
-0.83
Change Language
If two random variables $X$ and $Y$ are connected by relation $\frac{2 X-3 Y}{5 X+4 Y}=4$ and $X$ follows Binomial distribution with parameters $n=10$ and $p=\frac{1}{2}$, then what is the variance of $Y$ ?
A

$\frac{810}{361}$

B

$\frac{9}{19}$

C

$\frac{21}{361}$

D

$\frac{121}{361}$

EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12