A city currently has 131 streetlights. As part of an urban renewal program, the city council has decided to install 4 additional streetlights at the end of each week for the next 52 weeks.

Question

1. The city will have  streetlights at the end of 48 weeks.
2. The city will have 271 streetlights at the end of  weeks.

Answer 1

131+4(48)

= 131 + 192

= 323 street lights after 48 weeks, with 4 added each week starting with 131 at time zero

271= 131+4w

4w = 271-131= 140

w = 140/4 = 35 weeks = when there will be 271 street lights