Eight oranges can be bought for Rs. 10.40. How many more can be bought for Rs. 16.90 ?

Answer

To solve the problem step by step, we will use the unitary method to find out how many oranges can be bought for Rs. 16.90, and then determine how many more can be bought compared to the original amount.

### Step 1: Find the cost of one orange
Given that 8 oranges can be bought for Rs. 10.40, we first find the cost of one orange.

\[ \text{Cost of one orange} = \frac{\text{Total cost}}{\text{Number of oranges}} = \frac{10.40}{8} \]

### Step 2: Calculate the cost of one orange
Calculating the above expression:

\[ \text{Cost of one orange} = \frac{10.40}{8} = 1.30 \text{ Rs.} \]

### Step 3: Find how many oranges can be bought for Rs. 16.90
Now, we need to find out how many oranges can be bought for Rs. 16.90. We will use the cost of one orange calculated in the previous step.

\[ \text{Number of oranges for Rs. 16.90} = \frac{\text{Total amount}}{\text{Cost of one orange}} = \frac{16.90}{1.30} \]

### Step 4: Calculate the number of oranges for Rs. 16.90
Calculating the above expression:

\[ \text{Number of oranges for Rs. 16.90} = \frac{16.90}{1.30} \approx 13 \]

### Step 5: Find how many more oranges can be bought
Now, we need to find out how many more oranges can be bought compared to the original 8 oranges.

\[ \text{Additional oranges} = \text{Oranges for Rs. 16.90} - \text{Original oranges} = 13 - 8 \]

### Step 6: Calculate the additional oranges
Calculating the above expression:

\[ \text{Additional oranges} = 13 - 8 = 5 \]

### Final Answer
Thus, the number of additional oranges that can be bought for Rs. 16.90 is **5**.

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