Salaries of 40 college graduates who took a statistics course in college have a mean of $62, 200. assuming a standard deviation of $11,766 construct a 90% confidence interval for estimating the population mean.

round to the nearest integer as needed.

Step-by-step explanation:

We want to determine a 90% confidence interval for the mean salaries of college graduates

Number of sample, n = 40

Mean, u = $62, 200

Standard deviation, s = $11,766

For a confidence level of 90%, the corresponding z value is 1.645. This is determined from the normal distribution table.

We will apply the formula

Confidence interval

= mean +/- z ×standard deviation/√n

It becomes

62200 +/- 1.645 × 11766/√40

= 62200 +/- 1.645 × 1860.4

= 62200 +/- 3060.358

The lower end of the confidence interval is 62200 - 3060.358 =59139.642

The upper end of the confidence interval is 62200 + 3060.358 =65260.358

Therefore, with 90% confidence interval, the mean mean salaries of college graduates is between $59139.642 and $65260.358

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.