mansi garg   11 years AGO

if birds were 81 then there square root is 9
bird flown=9
remaining bird =72
according to given condition (9+3)^2=144
and twice of remaining bird =144
hence ans is 81

Like? Yes (6) | No (1)  

Sundar Kumar   11 years AGO

Answer : option 7)81

Like? Yes (6) | No (2)  

anuradha   11 years AGO

Let total no. of birds = x
birds flown away= x^1/2
so, 2(x-(x^1/2)) = ((x^1/2)+(x^1/4))^2 ...(1)
as we can see here that we have to find 1/4th of a no.
so from option find the no.s which can give 1/4th a integer.
64,100,56,49,99,121,144 is not posible
16,81 could be ans
put both values in equatn (1) one by one.
81 satisfires the equation. so 81 is ans.

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Ranjit Somisetty   11 years AGO

x2 be the total birds
2.(x2-x)=(x+sqrt(x))2
on solving we get x=9
hence total birds = x2=81

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Vikash Kumar   11 years AGO

let total birds be x
Remainin birds sqr root of x
Equation
2(x-root x)=(root x +root of root x)^2
Use hit and trial method
81 is correct answer.

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Anupam Banerjee   11 years AGO

Let there were x birds on the tree.
So, the equation will be....

2*(x - sqrt x) = (sqrt x + sqrt(sqrt x))^2

So, x - 3x^1/2 -2x^3/4 = 0

The solution of the equation gives
x = 81;

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Shashi nath jha   11 years AGO

the equation is 2(x -sqrt(x))=(sqrt(x)-sqrt(sqrt(x)))^2.
on solving x=81.

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MANIKONDA SAI PRASANNA   11 years AGO

let total no of birds=x
accoding to the problem
2(x-x^1/2)=(x^1/2+x^1/4)^2
x=3x^1/2+2x^3/4
it is easy to verify the answers than by solving
x=81
81=3(9)+2(27)
81=81

Like? Yes (2) | No (1)  

Saraswathy   11 years AGO

Let y be the initial no. of birds nd x no. of birds flown away...
Then y=x^2 --->(1)
Birds left = y-x
2(y-x) = (x+sqrt(x))^2 --->(2)

Solving (1) nd (2),
We ll get x=9, y=81

Ans : 81 (Option 7)

Like? Yes (2) | No (1)  

CHETNA TUTEJA   11 years AGO

Let the total birds on tree be x
so as said x^1/2 birds flew away
remaining birds (x-x^1/2)
Now as per ques.
2 (x-x^1/2)=(x^1/2+x^1/4)^2
On solving the equatin we get,
x^1/4=3
So x=81, that is option (7) is correct

Like? Yes (1) | No   

Vaishali Gupta   11 years AGO

A.T.Q
2(x-x^1/2)=(x^1/2+(x^1/2)^1/2)^2
On solv,
X-3x^1/2=2x^3/4
X=81

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Syeda Tahaseen Naaz   11 years AGO

no. of birds moved away=square root of 81=9
remaining= 81-9=72
given :2( 72)=( 9+sqtr(9))2
144=144
hence no. of birds =81

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raghu   11 years AGO

2(x-srt(x))=(srt(x)+srt(srt(x)))^2
by checking options it would be 81 also double square root will be solved only by 81 since srt(81)=9 and srt(9)=3 in srt(srt(x)).

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bhagya sree   11 years AGO

Let 'x' be the no. of birds sitting on tree.
Then,
2(x-√x)= (√x)2 + √√x
By option verification, ans is 7)

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RISHABH SHARMA   11 years AGO

let initial birds on tree is x so...
2(x-x^1/2)=( x^1/2 + (x^1/2)^1/2 )^2

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Manikandan   11 years AGO

total - 100=> 100-2*2=100=>twice=>2(2*2)=>4*4=16=>96-16=80
Answer may be = around 80 or 81

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Mallikharjuna   11 years AGO

2(x-sqrt(x))=(sqrt(x)+sqrt(sqrt(x)))^2
by back substitution

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venkateswara   11 years AGO

total birds =x
away from tree =sqrt(x)
remaining=y=(x-sqrt(x))
2y=[(sqrt(x))+(sqrt(sqrt(x)))]^2
by solving
x=2*sqrt(x)(sqrt(sqrt(x))+1)+sqrt(x)
take 81 as x it will satisfy condition

Like? Yes (1) | No   

MRITUNJAY KUMAR   11 years AGO

let x be the total no. of birds sitting on the tree.
A/Q the question we get the eqn;
2(x-x^1/2)=(x^1/2+x^1/4)^2;this equation satisfied only when x=81.

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Rashmi bharti   11 years AGO

let n^4 birds r there.
n^2(n^2-2n-3)=0
=>n=3
n^4=81

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sam   11 years AGO

total birds=x
2(x-root x)=(root x+root of root x)^2
so we get x=81
so,lhs=rhs
X=81

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pawan kumar chhipa   11 years AGO

let total birds is x^2
flown birds is x
remaining birds is x^2-x
according to the question
(x+ square root of x)^2= 2(x^2-x)

solve it
x=9
so total bird is 81
ans is option 7) 81

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Ajay Kumar   11 years AGO

let no of birds=x, after (x)^1/2 birds moves away there are only (x-sqrt(x)) birds remain.
Acording to the question
(x-sqrt(x))*2=(sqrt(x)+(x)^1/4)^2
2x-2sqrt(x)=x+sqrt(x)+2(x)^3/4
x-3sqrt(x)=2(x)^3/4
After squaring both sides, we get
x^2+9x-6(x)^3/2=4(x)^3/2
x^2+9x=10(x)^3/2
After taking x common from both sides, we get
x+9=10sqrt(x)
squaring both sides
x^2+81+18x=100x
x^2-82x+81=0
After solving this, we get
x=81,1

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T.Aravinth kumar   11 years AGO

Sub the values in following in equation
2(X-√X)-(√X+√√X)=0.

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IFFAT IRAM   11 years AGO

let the birds on the tree be x
2(x-x^(1/2))=(x^(1/2)+x^(1/4))^2
2(x-x^(1/2))=(x+x^(1/2)+2x^(3/4)
x-2x^(3/4)-3x^(1/2)=0
x^(1/2)(x^(1/2)-2x^(1/4)-3)=0
x^(1/2)-2x^(1/4)-3=0
y=x^(1/4)
y^2-2y-3=0
y^2-3y+y-3=0
(y-3)(y+1)=0
y=3 or -1

x^(1/4)=3
x=3^4
x=81

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Varunraj Reddy   11 years AGO

By verification Option 7) only satisfies the given
condition

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RAKESH   11 years AGO

2(x -√x) = (√x + √√x)^2

x should of form 2^4,3^4,4^4,...
from options, x=16, 81 are possible
x= 81 satisfies eqn.

Like? Yes (2) | No (2)  

sruthi   11 years AGO

7 is the answer

Like? Yes (1) | No (3)