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On the normal chess board as shown, I1, ...

On the normal chess board as shown, `I_1, & I_2`, are two insects whichstarts moving towards each other. Each insect moving with thesame constant speed. Insect `I_1`, can move only to the right or upwardalong the lines while the insect `I_2`, can move only to the left or downwardalong the lines of the chess board. Find the total number of ways thetwo insects can meet at same point during their trip.

A

A. `((9)/(8))((10)/(7))((11)/(6))((12)/(5))((13)/(4))((14)/(3))((15)/(2))((16)/(1))`

B

B. `2^(8)((1)/(1))((3)/(2))((5)/(3))((7)/(4))((9)/(5))((11)/(6))((13)/(7))((15)/(8))`

C

C. `((2)/(1))((6)/(2))((10)/(3))((14)/(4))((18)/(5))((22)/(6))((26)/(7))((30)/(8))`

D

D. `""^(16)C_(8)`

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AI Generated Solution

The correct Answer is:
To solve the problem of how many ways the two insects can meet on a chessboard, we can follow these steps: ### Step 1: Understand the movement of the insects Insect \( I_1 \) can move only to the right or upward, while insect \( I_2 \) can move only to the left or downward. They start at opposite corners of the chessboard. ### Step 2: Set the positions Assume insect \( I_1 \) starts at the bottom-left corner (0,0) and insect \( I_2 \) starts at the top-right corner (8,8) of an 8x8 chessboard. ### Step 3: Determine the total distance Both insects need to travel across the chessboard. The total distance each insect needs to cover is 8 units horizontally and 8 units vertically, making a total of 16 moves. ### Step 4: Calculate the number of steps The insects can meet at any point on the chessboard. However, the minimum number of steps for both insects to meet is 8 steps. This is because both insects must take 8 steps in total to meet at a point on the chessboard. ### Step 5: Use combinations to find the number of ways The total number of ways the two insects can meet is given by the combination formula \( C(n, r) \), where \( n \) is the total number of steps and \( r \) is the number of steps taken in one direction. Since both insects together take 16 steps (8 right/up for \( I_1 \) and 8 left/down for \( I_2 \)), we need to choose 8 steps from these 16 total steps. Thus, the number of ways they can meet is given by: \[ \text{Number of ways} = C(16, 8) \] ### Step 6: Final calculation Using the combination formula: \[ C(16, 8) = \frac{16!}{8! \cdot 8!} \] This gives us the total number of ways the two insects can meet at the same point on the chessboard. ### Conclusion Thus, the total number of ways the two insects can meet at the same point during their trip is \( C(16, 8) \). ---
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