CAT Exam Category

A drum has 40 kg of water, from this drum 4kg of water was taken out and
replaced by milk. This task was repeated nearly 2 times. How much water is now
contained by the drum?

Read Solution (Total 2)

29.16 kg as
Some of water in the Drum a is 40 kg
Some of water taken out b is 4 kg
No.of times = 3
Some of water in the Drum is { a[ 1 - (b/a) ]^n }kg
={ 40[ 1 - (4/40) ]^3 }kg
= 40 (9/10)^3 kg
= 40 ( 729/1000)
Some of water in the Drum = 29.16 kg
10 years agoHelpfull: Yes(4) No(0)

Initially total weight of water is 40kg
Now we are removing 10% (as 10% = 4 kg of 40kg) so 90% water remains there
We are doing it for twice, Hence it will be

40*90*90/100^2
0.324=32.4 lit
10 years agoHelpfull: Yes(0) No(1)

CAT Other Question

A drum has a combination of 2 liquids X and Y in the proprtion 7:5 when 9 L of
combination are taken out and the Drum is filled with Y, the proportion of X and Y
becomes 7:9. Then how many litres of liquids X was obtained by the Drum initially?
40 lires of milk contsin 5:3.if 8 litres of mixture be replaced by 8 litres of milk ...find ratio of milk and water in new mixture will be?