For every question, four probable answers as (A), (B), (C) and (D) are given. Only one out of these is correct. Choose the correct answer.
A park is 1500 metres long and 750 metre wide. A cyclist has to take four rounds this park. How much time he will take at the speed of 4.5 km/h?

Options

A. 40 hours
B. 20 hours
C. 10 hours
D. 4 hours

Answer

To solve the problem step by step, we need to find the time taken by a cyclist to complete four rounds of a park with given dimensions at a specific speed.

### Step 1: Calculate the perimeter of the park.
The park is rectangular, and the perimeter (P) can be calculated using the formula:
\[ P = 2 \times (length + width) \]

Given:
- Length = 1500 meters
- Width = 750 meters

Substituting the values:
\[ P = 2 \times (1500 + 750) \]
\[ P = 2 \times 2250 \]
\[ P = 4500 \text{ meters} \]

### Step 2: Calculate the total distance for four rounds.
Since the cyclist takes four rounds, the total distance (D) covered is:
\[ D = 4 \times P \]
\[ D = 4 \times 4500 \]
\[ D = 18000 \text{ meters} \]

### Step 3: Convert the distance from meters to kilometers.
To convert meters to kilometers, we divide by 1000:
\[ D = \frac{18000}{1000} \]
\[ D = 18 \text{ kilometers} \]

### Step 4: Calculate the time taken using the speed.
We know the speed (S) of the cyclist is 4.5 km/h. The formula for time (T) is:
\[ T = \frac{D}{S} \]

Substituting the values:
\[ T = \frac{18 \text{ km}}{4.5 \text{ km/h}} \]
\[ T = 4 \text{ hours} \]

### Final Answer:
The cyclist will take **4 hours** to complete four rounds of the park.

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