A. The point estimate of μ1 − μ2 is calculated using the value of x1 - x2, therefore:
μ1 − μ2 = x1 – x2 =
7.82 – 5.99
μ1 − μ2 = 1.83
B. The formula for
confidence interval is given as:
Confidence interval
= (x1 –x2) ± z σ
where z is a value
taken from the standard distribution tables at 99% confidence interval, z =
2.58
and σ is calculated
using the formula:
σ = sqrt [(σ1^2 /
n1) + (σ2^2 / n2)]
σ = sqrt [(2.35^2 /
18) + (3.17^2 / 15)]
σ = 0.988297
Going back to the
confidence interval:
Confidence interval
= 1.83 ± (2.58) (0.988297)
Confidence interval
= 1.83 ± 2.55
Confidence interval
= -0.72, 4.38
Answer:
x=√139-3, x=-√139-3
Step-by-step explanation:
to complete the square, you first move the constant to the other side of the equation-its already done for you!
now, you find the perfect square trinomial. You divide the b value by 2, then square it: 6/2=3, 3^2=9.
What you do to one side has to be done with the other.
x^2+6x+9=130+9
now you can factor the square:
(x+3)^2=139
squareroot both sides:
x+3=√139
x+3=-√139
now subtract both sides by 3
x=√139-3
x=-√139-3
Ur answr would be 154.50 because if u do 30.90 5 times or times 30.90 by 5 its 154.50
