A car moves at the speed of 72km/hr after repairing and moves at the speed of 54km/hr before repairing. It covers distance x in 6 hours after repairing. How much time (in hours) will it take to cover 3x distance before repairing?

Options

A. 20
B. 24
C. 18
D. 21

Answer

To solve the problem step by step, let's break it down:

### Step 1: Calculate the distance x covered after repairing
The car moves at a speed of 72 km/hr after repairing and covers distance x in 6 hours.

Using the formula for distance:
\[ \text{Distance} = \text{Speed} \times \text{Time} \]
We can substitute the values:
\[ x = 72 \, \text{km/hr} \times 6 \, \text{hours} = 432 \, \text{km} \]

### Step 2: Calculate the distance 3x
Now, we need to find the distance for 3x:
\[ 3x = 3 \times 432 \, \text{km} = 1296 \, \text{km} \]

### Step 3: Calculate the time taken to cover 3x before repairing
Before repairing, the car moves at a speed of 54 km/hr. We need to find the time taken to cover the distance of 1296 km.

Using the formula for time:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]
Substituting the values:
\[ \text{Time} = \frac{1296 \, \text{km}}{54 \, \text{km/hr}} = 24 \, \text{hours} \]

### Final Answer
The time taken to cover 3x distance before repairing is **24 hours**.

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