Answer: $85,000
Step-by-step explanation:
Given : In a given population of two-earner male-female couples, male earnings have a mean of $40,000 per year and a standard deviation of $12,000.

Female earnings have a mean of $45,000 per year and a standard deviation of $18,000.

If C denote the combined earnings for a randomly selected couple.
Then, the mean of C will be :-

Hence, the mean of C = $85,000
In order to figure this out you need to use
Descartes Rule. I attached a picture showing Descartes Rule. If the signs changes for when x is positive then the number of times it changes are the possible positive solution. If the sign changes when x is negative then the number of times it changes are the possible negative solutions. With that said the answer is A. View the picture I have attached for the possible + - and imaginary solutions.
Answer = A) One possible positive solution.
Answer:
x =53.85
Step-by-step explanation:
Let x be the original price
If the price is 22% of, you will pay 100% -22% = 78%
x * 78% = 42
Change to decimal form.
78x = 42
Divide each side by .78.
78x/.78 = 42/.78
Rounding to the nearest cent
x =53.85
Answer:

Step-by-step explanation:








