a palindrome is a number that reads the same forward and backward , such as 171 . how many even , 6 - digit numbers are palindromes ?
"first recognize you only need to consider the first three digits ( because the second three are just the first three flipped ) there are 900 possibilities for the first three digits of a 6 digit number , 100 - 999 inclusive . everything starting with a 2,4 , 6,8 will be even , which is 4 / 9 ths of the combinations . 4 / 9 * 900 = 400 answer : c"
divide(power(const_10, divide(6, const_2)), const_2)