Question

Find the smallest value of k such that 54k is the perfect square

Answer 1

Answer:

any number whose sum of digits is divible by 9 must itself be divisible by 9. if we add the digits of the number we get 1+5+7+5=18 which is a multiple of 9 so it must be divisible by 9. therefore k must be equal to 7 to make it a perfect square. hence 7 is the smallest number to make it a perfect square.