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

need: abcdcba
2 options for a (5 and 6)
3 options for b - (0, 5, and 6)
3 options for c - (0, 5, and 6)
3 options for d - (0, 5, and 6)
1 option for c after d (same digit used for c before d)
1 option for b after d (same digit used for b before d)
1 option for a after d (same digit used for a before d)
Overall: 2*3*3*3*1*1*1=54
Answer D

---