Question

What is a good estimate for the square root of 51?

Answer 1

Estimate 51 to the nearest 10 and get it from there?

Answer 2

10

Answer 3

Hint 51 is very close to 49

Answer 4

- and square root of 49 is what?

Answer 5

7

Answer 6

so square root of 51 will be a little bigger than 7

Answer 7

one pretty good method of doing this is to take the next perfect square after 49 which is 64 Then subtract them: 64-49=15 . Now 51-49 = 2 .
Now we add 2/15 to 7 . 2/15 = 0.13.
so we get 7 + 0.13 = 7.13 as the estimate.

Answer 8

If you square 7.13 on your calcukator you get 50.84 Pretty close to 51!

Answer 9

This method is called linear interpolation.