Question

If it is possible to form a number which is a perfect square of a two digit odd number using the second, fourth, seventh digits of the number 739142658 using each only once, which of the following is the second digit of that two-digit odd number?

A) 4 B) 7 C) 3 D) none

Answer 1

Square root problem

Given: the given number is 739142658

To find: If it is possible to form a number which is a perfect square of a two digit number using the second, fourth, seventh digits of the number 739142658 using each only once, which of the following is the second digit of that two digit number?

Solution:

• The given number is 739142658.
• The mentioned digits are 3, 1 and 6.
• We can form six numbers 136, 163, 316, 361, 613 and 631 using 1, 3 and 6.
• Of these numbers, 361 is a perfect square of the odd number 19, whose second digit is 9.

Answer: Option D) none .