An example of a direct variation scenario is the increase in the income of a start-up bakeshop when the number of cakes sold increase. Example data are (4, $ 100), (5, $ 125), (6, $ 150), and (7, $ 175).
The example of indirect variation scenario is the decrease in time it takes to reach a destination when the speed of the mobile increases. This is shown in the data points: (10 kph, 10 mins), (12 kph, 8 mins), (14 kph, 6 mins), and (16 kph, 4 mins).
Locate the y-intercept on the graph and plot the point.
From this point, use the slope to find a second point and plot it.
Draw the line that connects the two points.
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