Correct Answer: C

Rationale: To find the number of hosts in the restaurant, first, express the ratio algebraically as 9x + 2x + 1x = 36, where x represents the common factor. Combine like terms to get 12x = 36. Solve for x by dividing both sides by 12 to get x = 3. To find the number of hosts, multiply the coefficient of hosts (2) by x, which equals 6. Therefore, there are 6 hosts at the restaurant. Choice A, 3, is incorrect as it represents the number of servers. Choices B and D are incorrect as they do not correspond to the number of hosts based on the given ratio.

Correct Answer: C

Rationale: To calculate the total potential savings: First, find the 20% discount on the list price of $26,580: 0.20 $26,580 = $5,316. Then, determine the savings over the first 3 months of payments: 3 months $250/month = $750. Add the discount and the monthly payment savings to get the total potential savings: $5,316 + $750 = $6,066. Therefore, the correct answer is $6,066. Choice A, $1,282, is incorrect because it does not account for the total savings from both the discount and the monthly payments. Choice B, $5,566, is incorrect as it miscalculates the total savings by excluding the savings from the monthly payments. Choice D, $20,514, is incorrect as it does not consider the discount and only focuses on the list price.

Correct Answer: C

Rationale: To find the number of hosts in the restaurant, first, express the ratio algebraically as 9x + 2x + 1x = 36, where x represents the common factor. Combine like terms to get 12x = 36. Solve for x by dividing both sides by 12 to get x = 3. To find the number of hosts, multiply the coefficient of hosts (2) by x, which equals 6. Therefore, there are 6 hosts at the restaurant. Choice A, 3, is incorrect as it represents the number of servers. Choices B and D are incorrect as they do not correspond to the number of hosts based on the given ratio.

Correct Answer: A

Rationale: Let s be the number of sandwiches sold. Each sandwich earns $4, so selling s sandwiches at $4 each results in revenue of $4s. Similarly, d drinks at $2 each give $2d of income, and cookies bring in $1c. Summing these values gives total revenue = 4s + 2d + 1c. Therefore, option A, r = 4s + 2d + 1c, correctly represents the shop's revenue. Choices B, C, and D are incorrect because they incorrectly multiply the prices of each item by more than one day's sales, which would overstate the total revenue for a three-day period.

Correct Answer: C

Rationale: To solve the equation 3x + 4 = 19, first, subtract 4 from both sides to isolate the term with x, which gives 3x = 15. Then, divide both sides by 3 to solve for x, resulting in x = 5. Therefore, the correct answer is x = 5. Choice A, x = 3, is incorrect as it does not satisfy the equation. Choice B, x = 4, is also incorrect as it does not make the equation true. Choice D, x = 6, is incorrect as it does not align with the correct solution obtained through the proper algebraic steps.