A truck covers a certain distance in 12 hours at the speed of 70km/hr . What is the average speed of a car which travels a distance of 120 km more than the truck in the same time ?

Options

A. 56km/hr.
B. 75km/hr.
C. 82 km/hr.
D. None of these

Explanation

To solve the problem step by step, we can follow these calculations:

### Step 1: Calculate the distance covered by the truck.
The truck travels at a speed of 70 km/hr for 12 hours.

\[ \text{Distance} = \text{Speed} \times \text{Time} \]
\[ \text{Distance} = 70 \, \text{km/hr} \times 12 \, \text{hours} = 840 \, \text{km} \]

### Step 2: Determine the distance covered by the car.
The car travels 120 km more than the truck in the same time (12 hours).

\[ \text{Distance covered by the car} = \text{Distance covered by the truck} + 120 \, \text{km} \]
\[ \text{Distance covered by the car} = 840 \, \text{km} + 120 \, \text{km} = 960 \, \text{km} \]

### Step 3: Calculate the average speed of the car.
The average speed is calculated using the formula:

\[ \text{Average Speed} = \frac{\text{Distance}}{\text{Time}} \]
\[ \text{Average Speed of the car} = \frac{960 \, \text{km}}{12 \, \text{hours}} = 80 \, \text{km/hr} \]

### Final Answer:
The average speed of the car is **80 km/hr**.

---