Question

what could be the possible ones digit of the square root of 576
a. 4,6
b. 5,7
c. 1,8
d. 2,9​

Answer 1

To Find:

• The possible ones digit of the square root of 576.

a) 4, 6

Squaring both the numbers.

• 4² = 16
• 6² = 36

Here, we found that both have common ones digit.

And also the ones digit of both the number is 6.

b) 5, 7

Squaring both the numbers.

• 5² = 25
• 7² = 49

Ones digit of both the number is not 6.

c) 1, 8

Squaring both the numbers.

• 1² = 1
• 8² = 64

Ones digit of both the number is not 6.

d) 2, 9

Squaring both the numbers.

• 2² = 4
• 9² = 81

Ones digit of both the number is not 6.

Hence,

• a) 4, 6 could be the possible ones digit of the square root of 576 .

Answer 2

Given :-

A number 576

To Find :-

Possible ones digit of the square root

Solution :-

The rule for finding the possible ones digit of the square root is :-

The last digit of the given number should be the same as the square of the given numbers.

For ex

484 = Ones digit = 4

(2)² = 4

(8)² = 64 = Ones digit = 4

Now, Coming to the question

576

①

4,6

576 = Ones digit = 6

(4)² = 16 = Ones digit = 6

(6)² = 36 = Ones digit = 6

②

576 = Ones digit = 6

(5)² = 25 = Ones digit = 5

(7)² = 49 = Ones digit = 9

③

576 = Ones digit = 6

(1)² = 1 = Ones digit = 1

(8)² = 64 = Ones digit = 8

④

576 = Ones digit = 6

(2)² = 4 = Ones digit = 4

(9)² = 81 = Ones digit = 1

As we can see only Option no. A has the same ones digit. Therefore,

Option A is correct