So 90 is 4/5 of a number.
4/5n=90
4n=450
n=450/4
n=112.5
Answer:
Paired difference t test
Step-by-step explanation:
The paired difference t test is a type of statistical test which is used to examine if difference exists in th population mean of two samples. The paired difference test usually involves samples taken within subjects. That is, the sample mean for each set of measurement is taken from the Same subject, In the scenario described above, the subjects which are the 6 veteran runners each wore each of the two shoe brands, this means that two readings were produced by each runner ; one reading for brand A and the other brand B.
The difference between the two readings are taken for each runner and used to perform a hypothesis test:
t = μd/ (s/√n)
s = sample standard deviation ; n = sample size ; μd = mean difference
We know that
[surface area of sphere]=4πr²
[surface area of hemisphere]=2πr²
(sphere)
r=12 in
[surface area of sphere ]=4π12²--------> 576π in²
(hemisphere)
r=12 in[surface area of hemisphere ]=2π12²--------> 288π in²
[the ratio of the surface area of sphere to the surface area of hemisphere]
=576π/288π-------> 2
the answer is
the ratio is 2
Answer:
12
Step-by-step explanation:
Given :
Male Female Total
Registered 60
Non registered 40
Total 20 80
Solution :
N= 100
Formula of expected frequency = 
= expected frequency for the ith row/jth columm.
= total in the ith row
= total in the jth column
N = table grand total.
So, using formula 









![E_{22]=\frac{80 \times 40}{100}](https://tex.z-dn.net/?f=E_%7B22%5D%3D%5Cfrac%7B80%20%5Ctimes%2040%7D%7B100%7D)

Expected frequency table
Male Female Total
Registered 12 48 60
Non registered 8 32 40
Total 20 80
So, the expected frequency for males who are registered voters are 