IBPS Clerk Prelims Model Paper 19

Let the original mixture of acid/ water be x litre.
Then, in (x + 1) litre of mixture, acid is 20%. Quantity of acid
= (x + 1) ×

20

100

= (

x+1

5

)
Again,

x+1 5 +1

x+2

× 100 =

100

3

or

x+1+5

5(x+2)

×100 =

100

3

or x + 6 =

5(x+2)

3

or 3x +18 = 5x +10
or 18 −10 = 5x = 3x
or 8 = 2x
or x = 4L
And quantity of acid =

4+1

5

= 1L
Percentage of acid in original mixture
=

1

4

×100 = 25 %