Find the wrong number in the following number series.
36,20,12,8,6,5.5,4.5

Options

A. A)8
B. B)36
C. C)5.5
D. D)4.5

Answer

To find the wrong number in the series 36, 20, 12, 8, 6, 5.5, 4.5, we will analyze the pattern step by step.

### Step 1: Identify the pattern
Let's observe the series:
- First term: 36
- Second term: 20
- Third term: 12
- Fourth term: 8
- Fifth term: 6
- Sixth term: 5.5
- Seventh term: 4.5

### Step 2: Calculate the differences
We will check how each term relates to the next:
1. From 36 to 20:
- \( 36 - 20 = 16 \)
2. From 20 to 12:
- \( 20 - 12 = 8 \)
3. From 12 to 8:
- \( 12 - 8 = 4 \)
4. From 8 to 6:
- \( 8 - 6 = 2 \)
5. From 6 to 5.5:
- \( 6 - 5.5 = 0.5 \)
6. From 5.5 to 4.5:
- \( 5.5 - 4.5 = 1 \)

### Step 3: Look for a consistent pattern
Now we can see that the differences are:
- 16, 8, 4, 2, 0.5, 1

This does not show a consistent pattern. However, let's try a different approach by checking if there is a multiplication or division pattern.

### Step 4: Check for a multiplication/division pattern
Let's analyze the terms:
1. Starting with 36, if we subtract 4 and then multiply by 0.5:
- \( (36 - 4) \times 0.5 = 32 \times 0.5 = 16 \) (not matching)
2. Let's try another approach:
- From 36 to 20:
- \( 36 - 16 = 20 \)
- From 20 to 12:
- \( 20 - 8 = 12 \)
- From 12 to 8:
- \( 12 - 4 = 8 \)
- From 8 to 6:
- \( 8 - 2 = 6 \)
- From 6 to 5.5:
- \( 6 - 0.5 = 5.5 \)
- From 5.5 to 4.5:
- \( 5.5 - 1 = 4.5 \)

### Step 5: Identify the inconsistency
Notice that the expected pattern seems to be halving the previous difference:
- 16, 8, 4, 2, 1, (should be 0.5 but we have 5.5 instead)

If we follow the pattern:
- From 6, we should have:
- \( 6 - 1 = 5 \)

### Conclusion
The number 5.5 does not fit the pattern because if we followed the established differences, the term after 6 should be 5, not 5.5.

Thus, the wrong number in the series is **5.5**.