One herd of camels was seen in the forest, twice the square root of the herd had gone to mountains a

M4maths Previous Puzzles

09 Jul 2013 Problem

One herd of camels was seen in the forest, twice the square root of the herd had gone to mountains and the remaining 15 camels were seen on the bank of a river. Find the total number of camels.

OPtion

1) 15
2) 16
3) 20
4) 25
5) 36
6) 40
7) 49
8) 52
9) 64
10) None of these

Solution

Let total number of camels = x
2.sqrt(x) are on the mountain and remaining camels are 15
x-2.sqrt(x)=15
x-15=2.sqrt(x) (Squaring both side)
solve we get
x = 9 and x = 25
x cannot be 9 because 15 are remaining
The total camels are 25
option 4

Correct Option: 4 Best Solution (14)

Sagar Jinachandran   11 years AGO

let x be the number of camels in the herd
according to question we get
2x^(1/2)+15=x
2x^(1/2)=x-15
squaring both sides
4x=x2-30x+225
x2-34x+225=0
solving the equation we get
x=25, 9
since 9 is not in the option we get 25
option 4

Like? Yes (3) | No   

Angeline   11 years AGO

Let us consider X to be the Herd of camels:
2√x + 15 = x ----------> 1
(X – 15)^2 / 2 = x
(X^2 + 225 – 30x) / 4 = x
X^2 + 225 – 30x = 4x
X^2 + 225 – 30x – 4x = 0
X^2 + 225 – 34x = 0
X^2 – 34x + 225 = 0
X^2 – 9x – 25x + 225 = 0
X(x-9) – 25(x-9) = 0
(x-25) & (x-9) => x=25 or 9
Hence by substituting both the values in equation 1
2√25 + 15 = 25 2√9 + 15 = 9
2*5 + 15 = 25 2*3+ 15 = 9
10 + 15 = 25 ---->2 6 + 15 = 21---->3
Hence we obtain the X value by substituting 25 from equation 2 hence the option is 4) 25

Like? Yes (3) | No (1)  

FRANKLIN VIJAY   11 years AGO

2sqrx+15=25

Like? Yes (2) | No (1)  

Dhivya   11 years AGO

Let us consider X to be the Herd of camels:

2√x + 15 = x -----------------> 1
then √x= (x-15)/2
so x= ((x-15)/2)^2

(X^2 + 225 – 30x) / 4 = x
X^2 + 225 – 30x = 4x
X^2 + 225 – 34x = 0
X^2 – 34x + 225 = 0
Then by solving we get
X^2 – 9x – 25x + 225 = 0
X(x-9) – 25(x-9) = 0
x= 25 or x = 9

Hence by substituting both the values in equation 1
When x=25
2√25 + 15 = 25 -----------(2)
Or when x=9
2√9 + 15 =9 ----------(3)
Hence the equation (2) satisfies the condition so the value will be 25 camels.

Like? Yes (2) | No (1)  

pravallika nathi   11 years AGO

x-2sqrt(x)=15

Like? Yes (1) | No   

Jigyasa Kumar   11 years AGO

Let the x be the total no. of camels
2sqrtx +15 = x
so the answer is 25

Like? Yes (2) | No (1)  

Aarush Singh   11 years AGO

Let the x be the total no. of camels
2sqrtx +15 = x
so the answer is 25

Like? Yes (2) | No (1)  

arpit farkya   11 years AGO

according to question let us assume the no. of cammels in one herd x
x=2*sqrt(x)+15
sox=25 and x=9

Like? Yes (1) | No   

shailesh kumar mishra   11 years AGO

LET X IS THE HERD OF CAMELS
THEN 2SQRX+15=X PUT SQRX = Y
THEN X=Y SQURE
YSQUARE-2Y-15=0
BY SOLVIND WE GET Y=-3 AND Y=5 BUT NUMBER SHOULD NOT BE IN NEGETIVE SO Y=5 AND X= 25 IS ANS

Like? Yes (1) | No (1)  

Roopam Jain   11 years AGO

let x be the total no. of camels
then :
x-2x^(1/2)=15
Let t = x^(1/2)
we have a simple quadratic equation:
t^2-2t-15=0
On solving t=5
Total no. of camels = x = t^2 = 25

Like? Yes (1) | No (1)  

Udhaya kumar   11 years AGO

2root of x =x - 15
We get 9,25....
Practically 25 is possible....

Like? Yes (1) | No (1)  

Ash   11 years AGO

2 * sqrt(x)+ 15
x takes the value 25

ans is 25.

Like? Yes (1) | No (1)  

krishnapriya   11 years AGO

given 2sqrt(c)+15=c---------(1)
squaring we get,
c^2-34c+225=0
solving the above, we get
c=25 (or) c=9
c=25 satisfies the (1) equation

Like? Yes (1) | No (1)  

Himanshu Kumar Gupta   11 years AGO

Let x^2 be total no. Of camels
Then according to question
2x+15=x^2
On solving the above equation we get x=5 and x=-3 since no. Of camels can't be negative so x^2=25 is ans.

Like? Yes (1) | No (1)