Question

Use the table to write an equation that relates the cost of lunch Y and the number of students X

Answer 1

In order to determine what is the equation which describes the values of the table, consider that the general form of the equation is:

y = mx

where m is the constant of proportionality between both variables x and y.

To calculate m you calculate the quotient between any pair of data from the table.

If you for example use the following values:

Students = 8.00

Lunch cost = 2

the constant of proportionality is:

m = 8.00/2 = 4.00

Next, you replace the value of m in the equation y=mx:

y = $4.00x