Problem Solving (PS) | A palindrome is a number that reads the same forward and backward. For

Let the 7-digit number be a b c d c b a.

So, we only need to find out how many we can fill a, b, c and d, becausethe last three digits take the same number .
In addition to that, all a, b, c, and d have to be of the digits 5, 6 and 0 (repetition is allowed)

•a can take\(2\) numbers, which are 5 and 6. 0 is definitely out.
•b can take\(3\) numbers, which are 0, 5 and 6.
•c can take\(3\) numbers, which are 0, 5 and 6.
•d can take\(3\) numbers, which are 0, 5 and 6.

Thus, way to form a 7-digit
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