Answer:
[tex]y = 16 + 0.2t[/tex] --- the equation of SaveMore company
Step-by-step explanation:
Given
SaveMore
[tex]Initial = 16[/tex]
[tex]Additional\ Rate = 0.20[/tex]
Required
Determine the equation
Let
[tex]y \to cost[/tex]
[tex]t \to texts[/tex]
So, we have:
[tex]y = Initial + Additional\ Rate * t[/tex]
[tex]y = 16 + 0.20 * t[/tex]
[tex]y = 16 + 0.2t[/tex]
The equation for the second company is not given. So, the (b) part cannot be correctly answered.
A general solution to the (b) part is:
Assume the equation is:
[tex]y = 10 + 0.4t[/tex]
Next, we equate both
i.e.
[tex]y = y[/tex]
This gives:
[tex]16 + 0.2t = 10 + 0.4t[/tex]
Collect like terms
[tex]0.4t - 0.2t = 16 - 10[/tex]
[tex]0.2t = 6[/tex]
Divide by 0.2
[tex]t = 30[/tex]
Hence, the charges will be the same after 30 texts