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6 7 4 8 5 8 8 4 8 3 2 5 8 6 7 8 3 8 If...

6 7 4 8 5 8 8 4 8 3 2 5 8 6 7 8 3 8
If the 1st term of the above sequence is interchanged with the 2nd term the 3rd with the 4th and so on, then how many 8s are there that are divisible by the number on their left as well as their right

A

0

B

1

C

3

D

2

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will follow these instructions: ### Step 1: Interchange the terms of the sequence The original sequence is: 6, 7, 4, 8, 5, 8, 8, 4, 8, 3, 2, 5, 8, 6, 7, 8, 3, 8 We need to interchange the 1st term with the 2nd, the 3rd with the 4th, and so on. - Interchanging: 1st with 2nd: 7, 6 3rd with 4th: 8, 4 5th with 6th: 8, 8 7th with 8th: 4, 8 9th with 10th: 3, 2 11th with 12th: 5, 8 13th with 14th: 6, 7 15th with 16th: 8, 3 17th with 18th: 8, The new sequence after interchanging will be: 7, 6, 8, 4, 8, 8, 4, 8, 3, 2, 5, 8, 6, 7, 8, 3, 8 ### Step 2: Identify the 8s in the new sequence From the new sequence, we can see the positions of 8s: - 3rd position: 8 - 5th position: 8 - 6th position: 8 - 8th position: 8 - 12th position: 8 - 14th position: 8 - 16th position: 8 So, there are a total of **7** occurrences of 8 in the new sequence. ### Step 3: Check divisibility of each 8 by its left and right neighbors Now, we need to check each 8 to see if it is divisible by the numbers on its left and right: 1. **3rd position (8)**: Left = 6, Right = 4 - 8 is not divisible by 6 (8 % 6 ≠ 0) 2. **5th position (8)**: Left = 8, Right = 8 - 8 is divisible by both (8 % 8 = 0) 3. **6th position (8)**: Left = 8, Right = 4 - 8 is not divisible by 8 (8 % 8 = 0) but is divisible by 4 (8 % 4 = 0) 4. **8th position (8)**: Left = 4, Right = 3 - 8 is divisible by 4 (8 % 4 = 0) but not by 3 (8 % 3 ≠ 0) 5. **12th position (8)**: Left = 5, Right = 6 - 8 is not divisible by 5 (8 % 5 ≠ 0) 6. **14th position (8)**: Left = 6, Right = 3 - 8 is not divisible by 6 (8 % 6 ≠ 0) 7. **16th position (8)**: Left = 7, Right = None (no right neighbor) - Cannot be checked as there is no right neighbor. ### Step 4: Count the 8s that are divisible by both neighbors From the checks: - Only the 5th position 8 is divisible by both its left (8) and right (8). Thus, there is **only 1** occurrence of 8 that is divisible by both its left and right neighbors. ### Final Answer The total number of 8s that are divisible by the number on their left as well as their right is **1**. ---
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