M4maths Previous Puzzles

11 Dec 2014 Number of Birds

11 more than one fifth of the total birds flew away from a tree after that one third of the remaining birds came in the tree. If now there are 92 birds in the tree, then total no of birds remained in the tree after first fly away were

OPtion

1) 100
2) 80
3) 69
4) 58
5) 53
6) 50
7) 48
8) 46
9) 31
10)28

Solution

Let total number of birds after first fly away x
according to second condition
x + x/3 = 92
4x/3 = 92
x = 69

Option 3)

Correct Option: 3 Best Solution (18)

K.ARun   10 years AGO

let total no. of birds be x.
So, No. of birds flew=11+x/5.
Tota no. of birds Present now= x-(11+x/5)=> 4x/5-11
After that 1/3(4x/5-11) added back.
So, (4x/5-11)+1/3(4x/5-11)=> 4/3(4x/5 - 11)=92
On solving we get x=100.
So remaining birds after first fly away were= 4x/5-11=69

Like? Yes (8) | No (1)  

Ashwin Dinesh   10 years AGO

x + x/3 = 92
So x = 69
which is option 3)

Like? Yes (3) | No (2)  

Rahul   10 years AGO

suppose initially the number of birds are x
then after the first flew away the remaining will be (4x-55)/5
after the came back (16x-220)/15 which is equal to 92
thus , x=100
and the number of birds after first flew away will be 31
so remainig would be 100-31 = 69 :)

Like? Yes (1) | No   

Manasa Kotha   10 years AGO

11+x/5 birds flew away
11:23 AM
rest will be :@11+x/5)
rest will be X - (11+x/5)
so 4x/5-11 birds will be there
with that 1/3(4x/5 - 11) birds added
so 4/3 (4x/5 - 11)=92
we get x=100
so subst. x=100 we get 69

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Sravanthi   10 years AGO

let us assume total birds=x
92=(4/3)(x-(11+(1/5)x))
x=100
remaining birds after first fly=100-31=69

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Mithun Kumar Kesari   10 years AGO

69

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Srinivas Rao   10 years AGO

Total x
11 more than 1/5 th birds flew 11+1/5x
x-(11+x/5)+1/3(x-11-x/5)=92
solving x=100
Remaining birds remaining is 69 from equation

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BHASKAR MANDAL   10 years AGO

4/3(x-x/5 - 11) = 92
x=100
x-x/5-11 = 80-11 =69
option 3 is the answer

Like? Yes (2) | No (1)  

Anamika Purohit   10 years AGO

let the total number of birds =x
then according to the given condition,equation will be
11+1/5x
then 1/3*4/5x=4/15x
then 4/15x=92
x=345
1/5*345=69

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prudhvi vaddi   10 years AGO

69 birds remained in the tree after first fly away.
Total no.of birds =100
100-100/5-11=(500-100-55)/5= 3455=69 birds

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SHARAN KISHORE   10 years AGO

let the remaining birds be x, then 1/3 of x returned. So, x + x/3 = 92, x = 69

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Rishabh   10 years AGO

lets total number of birds is T.
T-((T/5)+11 number of birds remain in tree after first flew.
lets it suppose a.
now a+ a/3 = 92
after solving equation answer 69.

Like? Yes (2) | No (1)  

Rajat Rokade   10 years AGO

Total birds were 100. Now 31 birds flew away. So total remaining birds will be 100-31=69.
So, option 3 is correct.

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Pramod Gaikwad   10 years AGO

Total birds =100,
31 birds are fly away,
remaining birds is 69.
so option is 3)69.

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murari kumar   10 years AGO

Let total no of birds =x
no of birds after first fly= x-((x÷5)+11)
no of birds came after first fly= 1/3 (x-x÷5-11)
therefore ;
(x-x/5-11)+1/3(x-x/5-11)=92
after solving above eqation we get
x=100
hence no of birds after first fly = 69

Like? Yes (1) | No (1)  

Arul Shaijan   10 years AGO

Ans:69

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Anjali   10 years AGO

let the no of birds be x
birds flew away = 11+ (1/5)x = (55+x)/5
birds left on tree = x - (55+x)/5 -------------------(1)
birds on tree after some birds came in =
(1/3)( (4x-55)/5) + (4x-55)/5 = 92
it gives x=100
put x=100 in eq-1 we will get
birds left on tree = 69

Like? Yes (1) | No (1)  

Rahul Rathod   10 years AGO

Let us consider total no of birds=100
no of birds flew away=11+(1/5)*x=31
no of birds came =(1/3) of remaining(69)=23
so
no of birds on tree = 23+69=92
so 100-31=69
answer is option 3)69

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