An internet bill costs Rs.6 for 2 minutes 30 seconds. What is the cost in rupees for 3 minutes 20 seconds? (Round up to one decimal)

Options

A. 8
B. 7.9
C. 8.1
D. 8.2

Answer

To solve the problem of calculating the cost of internet usage for 3 minutes and 20 seconds based on the given rate for 2 minutes and 30 seconds, we can follow these steps:

### Step 1: Convert the time from minutes and seconds to seconds
First, we need to convert both time durations into seconds for easier calculations.

- For 2 minutes and 30 seconds:
\[ 2 \text{ minutes} = 2 \times 60 \text{ seconds} = 120 \text{ seconds} \]
\[ 30 \text{ seconds} = 30 \text{ seconds} \]
\[ \text{Total time} = 120 + 30 = 150 \text{ seconds} \]

- For 3 minutes and 20 seconds:
\[ 3 \text{ minutes} = 3 \times 60 \text{ seconds} = 180 \text{ seconds} \]
\[ 20 \text{ seconds} = 20 \text{ seconds} \]
\[ \text{Total time} = 180 + 20 = 200 \text{ seconds} \]

### Step 2: Determine the cost per second
Next, we find out how much it costs for 1 second based on the given cost for 150 seconds.

- The cost for 150 seconds is Rs. 6.
- To find the cost per second:
\[ \text{Cost per second} = \frac{6 \text{ Rs}}{150 \text{ seconds}} = \frac{6}{150} = 0.04 \text{ Rs/second} \]

### Step 3: Calculate the total cost for 200 seconds
Now, we can calculate the cost for 200 seconds using the cost per second we just calculated.

- The total cost for 200 seconds:
\[ \text{Total cost} = 200 \text{ seconds} \times 0.04 \text{ Rs/second} = 8 \text{ Rs} \]

### Final Answer
Thus, the cost for 3 minutes and 20 seconds is Rs. 8.