Answer:
5
Step-by-step explanation:
? x 2 = 10
/2 /2
? =5
Answer: 
Step-by-step explanation:
Given : Sample size : 
Sample mean : 
Standard deviation : 
Significance level : 
Critical value : 
Formula to find the confidence interval for population mean :-
Hence, a 90% confidence interval estimate of the population mean of all students =
Answer:
a=30 , b = 0
Step-by-step explanation:
let the two numbers be represented as a and b
a + b = 30... eqn 1
a - b = 30 ...... eqn 2
we then add the two equations to get values for a and b
a + b + a - b = 30 + 30
a + b + a -b = 60
2a = 60 ( diivide both sides by 2)
a = 30
we then put value for a = 30 into any of the equations to get b
a + b = 30, 30 + b= 30
b = 30 -30 , b = 0
to confirm if the answers are correct, we insert the values for a and b in the two equations.
a + b = 30..... eqn 1, 30 + 0 = 30
a - b = 30 ...... eqn 2 , 30 - 0 = 30
