IBPS SO Prelims Exam Model Paper 1

Given,
Capacity of the tank = 500 litres
Initial mixture =500×

3

10

=150
Remaining capacity = 500 – 150 = 350
Ratio of milk and water in initial mixture = 8 : 7
Time taken by milk pipe to fill the tank = 24 hours
Time taken by water pipe to fill the tank = 36 hours
Calculation:
Initial milk =

8

15

×150=80
Initial water = 150 – 80 = 70
Efficiency of milk pipe =

500

24

Efficiency of water pipe =

500

36

Time taken by milk and water pipe to fill completely =

350

500 24 + 500 36

= 10.08 hour
Value of milk in 10.08 hour =

500

24

×10.08 = 210 litres
Value of water in 10.08 hour =

500

36

×10.08 = 140 litre
Ratio of milk and water in full filled tank = (80 + 210) : (70 + 140) = 290 : 210
⇒ 29 : 21
∴ The new ratio of milk and water in full tank is 29 ∶ 21.