What should come in place of the question mark (?) in the following number series ?
(निम्नलिखित संख्या श्रृंखला में प्रश्नवाचक चिन्ह (?) के स्थान पर क्या आना चाहिए?)
`8000" "1600" "320" "64" "12.8" "?`

Options

A. `2.56`
B. `3.5`
C. `3.2`
D. `2.98`

Answer

To solve the number series: 8000, 1600, 320, 64, 12.8, ?, we will look for a pattern in the series.

### Step-by-Step Solution:

1. **Identify the first term and the second term:**
- The first term is 8000 and the second term is 1600.
- To find the relationship, we divide the first term by the second term:
\[ \frac{8000}{1600} = 5 \]
- This indicates that the second term is obtained by dividing the first term by 5.

2. **Identify the second term and the third term:**
- The second term is 1600 and the third term is 320.
- Again, we divide the second term by the third term:
\[ \frac{1600}{320} = 5 \]
- This shows that the third term is also obtained by dividing the second term by 5.

3. **Identify the third term and the fourth term:**
- The third term is 320 and the fourth term is 64.
- We divide the third term by the fourth term:
\[ \frac{320}{64} = 5 \]
- This confirms that the fourth term is obtained by dividing the third term by 5.

4. **Identify the fourth term and the fifth term:**
- The fourth term is 64 and the fifth term is 12.8.
- We divide the fourth term by the fifth term:
\[ \frac{64}{12.8} = 5 \]
- This indicates that the fifth term is also obtained by dividing the fourth term by 5.

5. **Find the next term (the term after 12.8):**
- Now, we will find the term that comes after 12.8 by dividing it by 5:
\[ \frac{12.8}{5} = 2.56 \]
- Therefore, the next term in the series is 2.56.

### Final Answer:
The term that should come in place of the question mark (?) is **2.56**.

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