Question

Without finding the square, find the unit digit in the square of 4626

Answer 1

Answer:

Let's try it...

Step 1:

What is the last number of 4,626? It is this number: 4626. The answer is 6. Is 6 in the list of numbers that are never perfect squares (2, 3, 7 or 8)?

Answer: NO, 6 is not in the list of numbers that are never perfect squares. Let's continue to the next step.

Step 2:

We now need to obtain the digital root of the number. Here's how you do it:

Split the number up and add each digit together:

4 + 6 + 2 + 6 = 18

If the answer is more than one digit, you would add each digit of the answer together again:

1 + 8 = 9

What is the digital root of number 4,626?

Answer: 9

Step 3:

So now we know the digital root of 4,626 is 9. Is 9 in the list of digital roots that are always a square root (1, 4, 7 or 9)?

Answer: YES, 9 is in the list of digital roots that are always perfect squares. We can conclude that 4,626 could be a perfect square!

Answer 2

The unit digit in the square of 4626 is 6