17, 9, 10, 22, 92, ?

Options

A. 744
B. 428
C. 318
D. 440

Explanation

To solve the series: 17, 9, 10, 22, 92, ?, we will look for a pattern in the numbers.

### Step-by-Step Solution:

1. **Identify the Pattern**:
- The series starts with 17, then goes to 9, followed by 10, 22, and 92.
- Notice that the first number (17) decreases to 9, and then the numbers start increasing.

2. **Analyze the Transition from 17 to 9**:
- From 17 to 9, we can see that 17 is halved and then adjusted.
- If we take 17, add 1 to it (17 + 1 = 18), and then halve it (18 / 2 = 9).

3. **Analyze the Transition from 9 to 10**:
- From 9 to 10, we simply add 1 (9 + 1 = 10).

4. **Analyze the Transition from 10 to 22**:
- From 10 to 22, we add 1 to 10 (10 + 1 = 11) and then double it (11 * 2 = 22).

5. **Analyze the Transition from 22 to 92**:
- From 22 to 92, we add 1 to 22 (22 + 1 = 23) and then multiply by 4 (23 * 4 = 92).

6. **Predict the Next Number**:
- Following the pattern, the next step after 92 would be to add 1 (92 + 1 = 93) and then multiply by 8 (since we are doubling the multiplier each time).
- So, we calculate: 93 * 8 = 744.

7. **Final Answer**:
- The last number in the series is **744**.