To solve this, we need to calculate how many liters of fuel the car would use for 1500 kilometers, then determine how many tanks of fuel that corresponds to.

1. Fuel consumption per kilometer: The car uses 9 liters per 100 kilometers. So, per kilometer, the car consumes:

   $\frac{9 \text{ liters}}{100 \text{ kilometers}} = 0.09 \text{ liters per kilometer}$

2. Fuel consumption for 1500 kilometers: The total fuel needed for 1500 kilometers is:

   $0.09 \times 1500 = 135 \text{ liters}$

3. How many tanks would be needed: Since one tank holds 68 liters, we calculate how many tanks are needed for 135 liters:

   $\frac{135}{68} \approx 1.985 \text{ tanks}$

   Therefore, you would need approximately 2 tanks to drive 1500 kilometers.

Would you like further details or explanations?

Here are some related questions:

1. How can fuel efficiency be improved to reduce consumption?
2. How does changing speed affect fuel usage?
3. How do different terrains (e.g., hills vs. flat roads) impact fuel consumption?
4. What impact does carrying extra weight have on fuel consumption?
5. How does the fuel efficiency of diesel engines compare to gasoline engines?

Tip: Regular maintenance, like checking tire pressure and replacing air filters