GID09 wrote:Daimaomee, sqrt(25-1.4^2) = 4.8.......any easy way of calculating this precisely??
Hi GID09, I have an "ancient" way to find the square root of a number:
(i) Separate the number in group of 2 digits (if it is a odd-digit number, leave the leftmost number as single-digit)
(ii) Starting from the leftmost group, find a number which square is nearest to the group (in this case, 4, as 4x4 = 16 is closest to 23) (Balloon 1)
(iii) Subtract the square of that number from the group and write down the difference (7 in this case)
(iv) Draw down the second group next to the difference (704)
(v) Double the number pointed by Balloon 1 and write it on the left hand side of the difference (4 x 2 = 8 in this case, Balloon 2)
(vi) Find a number and place it next to the "8" and place the same number next to the "4" on the top (Balloon 3) such that the product of the number formed (88) and the newly added number on the top (8) is closest to 704. In this case 88x8 = 704 exactly.
Even if the number is not a perfect square, this method can still find an approximate number whose square is closest to that number.
Hope this helps.
