Question

A bird shooter was asked how many birds he had in his bag. He replied there were all sparrows but six, all pigeons but six, and all ducks but six. How many birds he had in his bag?
A. 9
B. 18
C. 27
D. 36

Answer 1

Hint:Here in this question we will simply assume one variable which will be the total number of birds in his bag then we will find all types of bird’s number in terms of that assumed variable.

Complete step-by-step answer:
Firstly we will assume total number of birds in his bag, so let it be ‘x’
As it is given that all sparrows are 6 in number so if we will subtract 6 from total birds then we can get sparrows in terms of assumed variable.
Therefore,number of sparrows in his bag= x-6
Similarly it is given that all pigeons but 6 in number so if we will subtract 6 from total birds then we can get pigeons in terms of assumed variable.
Therefore,number of pigeons in his bag= x-6
Similarly it is given that all ducks are 6 in number so if we will subtract 6 from total birds then we can get ducks in terms of assumed variable.
So, number of ducks in his bag= x-6
Therefore total number of birds in his bag= $x - 6 + x - 6 + x - 6$
Also we know that total number of assumed birds in his bag = x
$ \Rightarrow x = x - 6 + x - 6 + x - 6$
$ \Rightarrow x = 3x - 18$
Now we will take variable terms to one side.
$ \Rightarrow 3x - x = 18$
 $ \Rightarrow 2x = 18$
$ \Rightarrow x = \dfrac{{18}}{2} = 9$

So, the correct answer is “Option A”.

Note:Students may make mistakes by directly taking numbers of sparrows, pigeons and ducks as 6 in number and adding them but that will be absolutely wrong. So this thing must be kept in mind while solving these types of questions.