human
John uses 5 liters of fuel per km to travel. How many liters of fuel should John plan to use if he plans to travel on two trips of 30 km and 20 km?
assistant
How many liters of fuel will John use on the first trip? ** The first trip will use 30*5=<<30*5=150>>150 liters of fuel.
How many liters of fuel will John use on the second trip? ** The second trip will use 20*5=<<20*5=100>>100 liters of fuel.
How many liters of fuel will John use in total? ** The total liters of fuel are 150+100=<<150+100=250>>250 liters.
#### 250