Question

tony is joining the intelliapps service for buying productivity apps online. there are three pricing plans for apps:

• no plan with a high price per app
• basic plan with a low subscription fee and a moderate price per app
• premium plan with a high subscription fee and a low price per app

the following graphs show lines for the costs of the different plans on the same graph (numbers on the axes are not shown).

question 1: in the following graph, match the 3 lines to their plans.

graph with cost (y-axis) and number of apps (x-axis), showing three lines: dotted blue, dashed red, solid green

dotted blue line: no plan dropdown
dashed red line: dropdown
solid green line: dropdown

question 2: if tony needs to download a apps, what is the least expensive plan?

Explanation:

For Question 1:

1. Dotted blue line: It has a fixed starting cost (y-intercept) and a very low slope. This matches the Premium plan, which has a high fixed subscription fee and low per-app cost.
2. Dashed red line: It has a low starting cost (y-intercept) and a moderate slope. This matches the Basic plan, which has a low subscription fee and moderate per-app cost.
3. Solid green line: It has no starting cost (y-intercept = 0) and a very steep slope. This matches the No plan, which has no subscription fee but a high per-app cost.

For Question 2:

• When the number of apps (A) is very low: The dashed red line (Basic plan) is the cheapest, as it has a low initial cost and the high per-app cost of the No plan hasn't overtaken it yet.
• When the number of apps (A) is at the intersection point of the dashed red and solid green lines: The Basic and No plans cost the same.
• When the number of apps (A) is between that intersection and the intersection of the dashed red and dotted blue lines: The solid green line (No plan) is the cheapest.
• When the number of apps (A) is at the intersection of the dashed red and dotted blue lines: The Basic and Premium plans cost the same.
• When the number of apps (A) is very high: The dotted blue line (Premium plan) is the cheapest, as its low per-app cost makes it the most economical for large quantities.

Answer:

Question 1:

Dotted blue line: Premium plan
Dashed red line: Basic plan
Solid green line: No plan

Question 2:

• If A is very small (fewer apps than the first intersection point): Basic plan
• If A is between the first and second intersection points: No plan
• If A is very large (more apps than the second intersection point): Premium plan
• At the intersection points, two plans cost the same (either Basic/No or Basic/Premium)