Question

what is square root of 42.25

Answer 1

Always remember that any number ending with 25 can be a perfect square if it's other digits can be expressed in the form of n(n+1), that is, the product of a natural number multiplied by the next natural number. Moreover, it's square root is 10n+5. It has also been proved in 8th standard NCERT book. I am proving it here too.



So, using this, 42.25=4225/100. Now, in 4225, if we remove 25, the remaining digits are 42=6*7 =6(6+1). Hence, square root of 4225 is 10(6)+5 =65. So, square root of 4225/100=65/10=6.5.

Answer 2

Hey there!

Square root of 42.25

= √4225/100

Factors of 4225

 5 | 4225

 5 | 845

13 | 169

13 |  13

    |   1

= √4225/100

= √5 x 5 x 13 x 13/10 x 10

= 5 x 13 / 10

= 65/10

= 6.5      Ans.

Hope it helps You!