InterviewSolution
Saved Bookmarks
| 1. |
The sum of a number and its positive square root is 6/25. Find the number. |
|
Answer» Given: The sum of a number and its positive square root is 6/25. To find: the number.Solution:Let the number be ‘a’. ⇒ a + √a = 6/25 ⇒ √a = (6/25) – a Squaring both sides ⇒ a = 36/625 + a2 – 12a/25 ⇒ a2 – 37a/25 + 36/625 = 0 factorise by splitting the middle term. ⇒ a2 – a/25 – 36a/25 + 36/625 = 0 ⇒ a(a – 1/25) – (36/25) × (a – 1/25) = 0 ⇒ (a – 36/25)(a – 1/25) = 0 ⇒ a = 36/25 , 1/25 But only 1/25 is possible as its sum with its positive root is 6/25. Hence the number is 1/25. |
|