After how many km would the car run out of gasoline? In order to not run out of gasoline, one should refuel it if the supply has reached a level of 5L. After how many km will this point be reached?
Für diese Aufgabe benötigst Du folgendes Grundwissen: Linear function
First, you should represent the gasoline consumption by a linear function. It has the form f(x)=mx+b where x stands for the travelled distance and f(x) for the consumed gasoline. You can now determine the values of m and b by substituting two points from the table of values.
The following linear function yields the gasoline consumption for a given number of travelled kilometers:
f(x)=0.075⋅x
When is the fuel supply empty?
The tank holds 56 liters of gasoline. You may now insert this value as f(x) and calculate the associated x-value:
56746.667==0.075⋅x∣:0.075x
So the fuel will run out after about 746 km.
When should the car be refueled?
The car should be refueled, when there are 5 liters of gasoline in the tank. Since at the beginning, the tank holds 56 liters, the car will cosume exactly 51 liters until this point. You can insert this into the function just as above:
