1
JEE Main 2021 (Online) 26th February Evening Shift
Numerical
+4
-1
Change Language
Let X1, X2, ......., X18 be eighteen observations such
that $$\sum\limits_{i = 1}^{18} {({X_i} - } \alpha ) = 36$$ and $$\sum\limits_{i = 1}^{18} {({X_i} - } \beta {)^2} = 90$$, where $$\alpha$$ and $$\beta$$ are distinct real numbers. If the standard deviation of these observations is 1, then the value of | $$\alpha$$ $$-$$ $$\beta$$ | is ____________.
Your input ____
2
JEE Main 2021 (Online) 24th February Evening Shift
Numerical
+4
-1
Change Language
If the variance of 10 natural numbers 1, 1, 1, ....., 1, k is less than 10, then the maximum possible value of k is ________.
Your input ____
3
JEE Main 2020 (Online) 6th September Evening Slot
Numerical
+4
-0
Change Language
Consider the data on x taking the values
0, 2, 4, 8,....., 2n with frequencies
nC0 , nC1 , nC2 ,...., nCn respectively. If the
mean of this data is $${{728} \over {{2^n}}}$$, then n is equal to _________ .
Your input ____
4
JEE Main 2020 (Online) 4th September Evening Slot
Numerical
+4
-0
Change Language
If the variance of the following frequency distribution :

Class         : 10–20 20–30 30–40

Frequency :    2          x          2

is 50, then x is equal to____
Your input ____
JEE Main Subjects
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