Answer:
Assuming "x2" is x squared:
5x(x2-4x+2)
(5x(x2)+5x(-4x)+5x(2))
<u>5x^3-20x+10x</u>
For these polynomial multiplication problems, just distribute the number outside the parentheses.
Given:
Sample size, n = 40
Sample mean, xb = $6.88
Population std. deviation, σ = $1.92 (known)
Confidence interval = 90%
Assume normal distribution for the population.
The confidence interval is
(xb + 1.645*(σ/√n), xb - 1.645*(σ/√n)
= (6.88 + (1.645*1.92)/√40, 6.88 - (1.645*1.92)/√40)
= (7.38, 6.38)
Answer: The 90% confidence interval is (7.38, 6.38)
Answer: (-0.3) + 0.9= 0.6
Step-by-step explanation:
