Question

Sanjay consulted three electricians about upgrading the wiring in his home. Each electrician uses a linear formula that incorporates a flat base fee and an hourly rate to determine the cost of service. Those formulas are shown in the table.

Repair Cost Formulas
Electrician
Cost in y dollars for an x-hour service
1
y = 25 x + 30
2
y = 30 x + 25
3
y = 25 x + 20

Which statement is best supported by the table?
Each electrician charges a different hourly rate.
Each electrician charges a different base fee.
All three electricians charge the same hourly rate.
All three electricians charge the same base fee.

Answer 1

Each electrician charges a different base fee.

Reason: the base fees are 30, 25, and 20 (all different). The hourly rates are 25, 30, and 25 (not all different).