Answer: (110.22, 125.78)
Step-by-step explanation:
The confidence interval for the population mean is given by :-
Given : Sample size = 463
Significance level :
Critical value :
We assume that the population is normally distributed.
Now, the 90% confidence interval for the population mean will be :-
Hence, 99% confidence interval for the mean study time of all first-year students = (110.22, 125.78)
Answer:
Step-by-step explanation:
Given equation is,
x² + (p + 1)x = 5 - 2p
x² + (p + 1)x - (5 - 2p) = 0
x² + (p + 1)x + (2p - 5) = 0
Properties for the roots of a quadratic equation,
1). Quadratic equation will have two real roots, discriminant will be greater than zero. [(b² - 4ac) > 0]
2). If the equation has exactly one root, discriminant will be zero [(b² - 4ac) = 0]
3). If equation has imaginary roots, discriminant will be less than zero [(b² - 4ac) < 0].
Discriminant of the given equation =
For real roots,
p² + 2p + 1 - 8p + 20 > 0
p² - 6p + 21 > 0
For all real values of 'p', given equation will be greater than zero.