Estimation of difference among two means-illustration, Mathematics

A comparison of the wearing out quality of two types of tyres was obtained by road testing. Samples of 100 tyres were collected. The miles traveled until wear out were recorded and the results given were as follows

Tyres                           T1                                T2

Mean                x¯1 = 26400 miles        x¯2 = 25000 miles

Variance          S21= 1440000 miles    S22= 1960000 miles

Determine a confidence interval at the confidence level of 70 percent


1 = 26400

2 = 25000

Difference between the two means

(x¯1 - x¯2)  = (26400 - 25000)

= 1,400

Again we consider the absolute value of the difference among the two means

We calculate the standard error as given below:

 S(A - x¯B) = √{(s21/n1) + (s22/n2)}

            = √{(1,440,000/100) + (1,960,000/100)}

= 184.4

Confidence level at 70 percent is read from the normal tables as 1.04 (Z = 1.04).

Thus the confidence interval is calculated as given below:

= 1400 ± (1.04) (184.4) 

= 1400 ± 191.77

or (1400 - 191.77) to (1400 + 191.77)

1,208.23 ≤ X ≤ 1591.77

Posted Date: 2/19/2013 12:33:03 AM | Location : United States

Related Discussions:- Estimation of difference among two means-illustration, Assignment Help, Ask Question on Estimation of difference among two means-illustration, Get Answer, Expert's Help, Estimation of difference among two means-illustration Discussions

Write discussion on Estimation of difference among two means-illustration
Your posts are moderated
Related Questions
From a point P, two tangents PA are drawn to a circle with center O.If OP=diameter of the circle show that triangle APB is equilateral. Ans:    PA=PB (length of tangents

Q. How to Left shifts and right shifts a graph? Ans. When you're translating (shifting) a graph, it's easy to get subtracting and adding mixed up. It seems counter-intuiti

Can you think of some more advantages of peer interaction and child-to child learning? If you agree that children learn a lot from each other, then how can we maximise such oppo

Before independence, Bangladesh was called Ceylon East Pakistan Bhutan Bangalore Which of the following countries does not have a monarch as head of state? Canada Australia Eire

If the p th term of an AP is q and the q th term is p. P.T its n th term is (p+q-n). Ans:    APQ a p = q a q = p a n = ? a + (p-1) d = q a + (q-1) d = p

I need the coordinates for this equation Y=1/2-4

Before searching at series solutions to a differential equation we will initially require to do a cursory review of power series. So, a power series is a series in the form, .

Order to solve Mathematical Operations: Example: Solve the following equation: (4 - 2) + (3 x 4) - (10 ÷ 5) - 6 =  ____________ Solution: a.         Perform ma

The general solution to a differential equation is the most common form which the solution can take and does not take any initial conditions in account. Illustration 5: y(t) =

Some important issue of graph Before moving on to the next example, there are some important things to note. Firstly, in almost all problems a graph is pretty much needed.