Question

An electric company calculates a person's monthly bill from the number of kilowatt-hours (kWh), x, used. The function b(x) = { x < 200 0.10x, 0.15(x – 200) + 20, x > 200 determines the bill. How much is the bill for a person who uses 800 kWh in a month? O A. $90 O B. $110 O C. $60 O D. $80

Answer 1

Since x = 800kWh which is greater than 200, we use the function

b(x) = 0.15(x - 200) + 20

b(800) = 0.15(800 - 200) + 20

=0.15(600) + 20

= 90 + 20

=$110

option B is the correct answer