A and B are 20km apart. A can walk at an average speed of 4km/hour and B at 6km/hr. If they start walking towards each other at 7 a.m, when they will meet?

Options

A. 8.00 a.m
B. 8.30 a.m
C. 9.00 a.m
D. 10.00 a.m

Answer

To solve the problem step by step, we will follow these instructions:

### Step 1: Identify the distance between A and B.
The distance between A and B is given as 20 km.

**Hint:** Always start by noting the initial distance between the two moving objects.

### Step 2: Determine the speeds of A and B.
A walks at a speed of 4 km/hour, and B walks at a speed of 6 km/hour.

**Hint:** Write down the speeds of both individuals clearly to avoid confusion later.

### Step 3: Calculate the relative speed.
Since A and B are walking towards each other, we add their speeds to find the relative speed:
- Relative speed = Speed of A + Speed of B
- Relative speed = 4 km/hour + 6 km/hour = 10 km/hour.

**Hint:** When two objects move towards each other, their speeds combine, so remember to add them.

### Step 4: Use the formula for time.
To find the time it takes for A and B to meet, we can use the formula:
- Time = Distance / Speed
- Here, Distance = 20 km and Speed = 10 km/hour.

Calculating the time:
- Time = 20 km / 10 km/hour = 2 hours.

**Hint:** Make sure you use the correct formula for time, which is distance divided by speed.

### Step 5: Determine the meeting time.
They start walking towards each other at 7 a.m. If it takes them 2 hours to meet:
- Meeting time = Start time + Time taken
- Meeting time = 7 a.m. + 2 hours = 9 a.m.

**Hint:** Always add the time taken to the starting time to find the meeting time.

### Final Answer:
A and B will meet at **9 a.m.**

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