56, 91, 175, 417, 777

Options

A. 56
B. 91
C. 175
D. 417

Explanation

To determine which number in the series 56, 91, 175, 417, 777 is incorrect, we can analyze the numbers by checking if they are divisible by 7.

### Step-by-Step Solution:

1. **Identify the Numbers in the Series**:
The numbers given are: 56, 91, 175, 417, 777.

2. **Check Divisibility by 7**:
We will divide each number by 7 and see if they yield whole numbers (integers).

- For **56**:
\[ 56 \div 7 = 8 \]
(This is a whole number.)

- For **91**:
\[ 91 \div 7 = 13 \]
(This is a whole number.)

- For **175**:
\[ 175 \div 7 = 25 \]
(This is a whole number.)

- For **417**:
\[ 417 \div 7 \approx 59.5714 \]
(This is not a whole number; it has a decimal.)

- For **777**:
\[ 777 \div 7 = 111 \]
(This is a whole number.)

3. **Conclusion**:
From the calculations, we see that 56, 91, 175, and 777 are all divisible by 7, but 417 is not. Therefore, the number that is incorrect in the series is **417**.

### Final Answer:
The number that is wrong in the series is **417**.

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