Question

Item Price (dollars) $1,400 $2,400 $3,000 $4,400 Sales Tax (dollars) $112 $192 $240 $352 Based on the table, what is the rate of change? O The rate of change for the sales tax is $0.07 per dollar. O The rate of change for the sales tax is $0.08 per dollar. O The rate of change for the sales tax is $0.06 per dollar. The rate of change for the sales tax is $0.125 per dollar.

Answer 1

We know that the rate of change is a rate that describes how one quantity changes in relation to another quantity. If x is the independent variable and y is the dependent variable, then

`r\text{ = }\frac{Change\text{ in y}}{\text{Change in x}}\text{ = }(Y2-Y1)/(X2-X1)`

where (X1,Y1) and (X2,Y2) are points of our model.

So, in this case we have that:

`r\text{ = }\frac{Y2-Y1}{X2-X1_{}}\text{ = }(112-352)/(1400-4400)\text{ = }(240)/(3000)\text{ = 0.08}`

So, the correct answer is: the rate of change for the sales tax is $0.08 per dollar.