Question

The cost of burgers ​varies directly​ with the number

of burgers purchased. If 30 burgers cost $45.00, what is the price of 20 burgers?
Write an equation to represent the situation.
What would 20 burgers cost?

Answer 1

Answer: 30$

Explanation:

Use a proportion

30/45=20/x is what I used

Answer 2

The cost of 20 burgers is $30.

Explanation:

It is given that, the cost of burgers ​varies directly​ with the number of burgers.

This means that, according to the number of burgers purchased, the cost of the burger has been changed.

The cost of the 30 burgers = $45

Let us assume, the cost of the 20 burgers = x

In order to find the value of x, use rate formula :

Rate = Total cost of the burgers / No.of burgers.

⇒ 45/30

Similarly, the cost is x for 20 burgers

⇒ x/20

Comparing the two rates,

⇒ 45/30 = x/20

⇒ x = (45×20) / 30

⇒ x = 900 / 30

⇒ x = 30

Therefore, the cost of 20 burgers is $30.