human
A plumber bought 10 meters of copper and 5 more meters of plastic pipe. If each meter cost $4, how much did the plumber spent on the copper and plastic pipe?
assistant
How many meters of plastic pipe did the plumber buy? ** He bought 10 + 5 = <<10+5=15>>15 meters of plastic pipe.
How many meters of copper and plastic pipe did the plumber buy? ** The total meters of the copper and plastic pipe is 10 + 15 = <<10+15=25>>25.
How much did the plumber spend on the copper and plastic pipe? ** The plumber spent $4 x 25 = $<<4*25=100>>100 on copper and plastic pipe.
#### 100