You are a junior analyst at a tech startup. Use the mathematics of equivalent expressions, the distributive property, and order of operations to investigate two app subscription plans — then write a memo recommending the better deal.
Two streaming apps — StreamPro and StreamBasic — are competing for customers. Your manager asked you to investigate their pricing expressions, prove which expressions are equivalent, apply the distributive property, and calculate real costs for a chosen number of months. Work through four phases, fill every box, and finish with a pricing memo.
StreamPro advertises its family plan two ways: 2(x + 3) and 2x + 6. Your job is to verify these are equivalent by testing any value of x. If both expressions always give the same result, they are equivalent!
For x = 5: 2(5 + 3) = 2 × 8 = 16. 2(5) + 6 = 10 + 6 = 16. They match! Try x = 0, x = 10, x = 100 — they will always match because these expressions are equivalent (that is what 6.EE.4 means).
StreamBasic offers a discount: a(b + c) where a is the discount rate, b is the base price, and c is a service fee. Use the distributive property to expand and simplify. Enter your own values for a, b, and c.
For a = 3, b = 8, c = 4: 3(8 + 4) = 3·8 + 3·4 = 24 + 12 = 36. You distribute the 3 to each term inside the parentheses. Both ways give the same answer: 3 × 12 = 36. ✓
StreamPro costs 9.99n + 4.50 dollars, where n is the number of months subscribed. The 4.50 is a one-time setup fee. Substitute your chosen n and evaluate — respecting order of operations (multiply before adding).
At n = 6: first, 9.99 × 6 = 59.94 (multiplication first!). Then 59.94 + 4.50 = 64.44. The setup fee is added only once at the end. Total cost = $64.44 for 6 months.
Compare StreamPro (9.99n + 4.50) vs StreamBasic (7.50n + 12.00) for the same number of months. Which is cheaper in the short term? Which is cheaper long-term? Then pass the quick-check.
Write a 3–5 sentence pricing memo to your manager. Explain your findings using real numbers and expressions from your calculations above.
| Category | 4 — Expert | 3 — Proficient | 2 — Developing |
|---|---|---|---|
| Equivalent Expressions (6.EE.4) | Equivalence verified for multiple x values with reasoning | Equivalence confirmed for one x value | Attempted but result was incorrect |
| Distributive Property (6.EE.3) | Expansion shown step by step and result verified both ways | Expansion is correct | Minor distribution error |
| Evaluating & Order of Operations (6.EE.2c) | Cost calculated correctly; order of operations explained | Cost value is correct | Attempted but operation order wrong |
| Communication | Memo clearly recommends a plan using every computed value | Memo uses most computed values | Memo is vague or missing key numbers |