Solve
-When Making a Telephone Call Using a Calling Card $\$ 2.10$

question 77

Multiple Choice

Solve.
-When making a telephone call using a calling card, a call lasting 4 minutes costs $\$ 2.10$ . A call lasting 11 minutes costs $\$ 4.90$ . Let $y$ be the cost of making a call lasting $x$ minutes using a calling card. Write a linear equation that relates cost $y$ to time $x$ .

• A) \(y = 0.4 x - 6.1\)
• B) \(y = 0.4 x + 0.5\)
• C) \(y = - 0.4 x + 3.7\)
• D) \(y = \frac { 5 } { 2 } x - \frac { 79 } { 10 }\)

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Definitions:

Utility-maximizing

A principle in economics where consumers aim to get the greatest satisfaction from their spending, given their budget constraint.

Goods

Tangible items that are produced and are capable of being physically delivered to a consumer.

Px(MUx)

This expression denotes the price of a good (Px) multiplied by its marginal utility (MUx), commonly used in economic analysis of consumer choice.

MUx/MUy

Represents the marginal utility of good x relative to the marginal utility of good y, often used in consumer choice theory to analyze optimum consumption points.