## Task 1 - 340611

Mr. Eilig drove a distance of 475 kilometers on the highway. He covered this distance in 3 hours and 10 minutes and used 57 liters of gasoline.

a) What was his average speed?

b) How much gasoline did he consume on average per $100 \mathrm{~km}$?

c) If he had driven with an average speed of $120 \mathrm{~km} / \mathrm{h}$, he would have consumed only 8 liters per $100 \mathrm{~km}$.

How far could he have driven with the saved gasoline at an average speed of $120 \mathrm{~km} / \mathrm{h}$?
a) Since Mr. Eilig needed 3 hours and 10 minutes, i.e., 19 times 10 minutes, for 475 kilometers, he drove on average $475: 19=25$ kilometers every 10 minutes, and thus $6 \cdot 25=150$ kilometers per hour; i.e., his average speed was $150 \mathrm{~km} / \mathrm{h}$.

b) Since he needed $57=3 \cdot 19$ liters of gasoline for the $475=25 \cdot 19$ kilometers, it was on average 3 liters for every 25 kilometers, and thus four times as much for every 100 kilometers, i.e., 12 liters.

c) If he had only needed 8 liters for every 100 kilometers, he would have saved 4 liters for every 100 kilometers. Since this is half of 8 liters, he could have driven an additional half the distance of the total distance of 475 kilometers.

Since $475=474+1$ and $474: 2=237$, this is 237 kilometers and half a kilometer (500 meters).