Answer: -3.0593
Step-by-step explanation:
The test statistic for the difference between two population mean (when population standard deviations 
are known ) is given by :-
where ,
= Sample sizes taken from two populations 1 and 2.
= Difference between two Sample mean.
= Standard deviations of populations 1 and 2.
As per given , we have
We assume that the data follows a normal distribution.
Then, the test statistic will be :-
Hence, the test statistic= -3.0593
3/4 * 5/7 = 15/28 or 0.5357
G (x) = x + 1 (fog) (x) = x 2 + 3x + 1 ⇒ (fog) (x) = x 2 + 3x + 1 ⇒ f (g (x)) = x 2 + 3x + 1 ⇒ f (x + 1) = x 2 + 3x + 1 Eg x + 1 = p, then x = p - 1. ⇒ f (p) = (p - 1) 2 + 3 ( p - 1) + 1 ⇒ f (p) = p 2 - 2p + 1 + 3p - 3 + 1 ⇒ f (p) = p 2 + p - 1 So f (x) = x 2 + x - 1 - ->
ANSWER IS : x 2 + x - 1
