Question

The total cost of hiring beth’s Plumber services is represented by the equation C= 50t + 70 where C is the total cost in dollar and t is the time in hours. Next month the rate change $60 per hour but the initial charge will stay the same. Which equation represents the new cost structure.

A. C =50t -70. C. C = 50t + 60
B. C = 60f + 70. D. C = 60t -70

Show proof of how u got that answer or evidence

Answer 1

Option B.
`C = 60t + 70`

Explanation:

Given:

The total cost of hiring Beth's Plumber services is expressed as:

`C = 50t + 70`

Here, the coefficient of
`t` represents the rate per hour and the constant term represents the initial charge.

So, when the rate per hour changes from 50 to 60, this means the coefficient of
`t` changes from 50 to 60. But, there is no change in the initial charge. So, 70 remains the same as the original equation.

∴ New equation is given as:

`C = 60t + 70`

Hence, option B is correct.