## Alligation in Time and distance

**Problem 3**

### Solution –

Solving this problem by alligation is a matter of just a few seconds, here’s how.

As you can see in the picture, weighted average speed is 50 km/h so we keep it in the middle. Average speed of bicycle and car is taken as in visual components. We take average speed of bicycle on the left side and average speed of car on the right side (rule of thumb). By solving this simple alligation we find that ratio of time the man takes to complete the journey by bicycle and car is 2:3. But here we need to find the ratio of distance covered, so 2*20= 40 and for car 3*70=210

**Ratio comes out to be 4:21**.

**Problem 4** – This is from the practice section from PERCENTAGE notes given in website..pls help to solve either in alligation method or any

A water tank contains 5% salt by weight. x litres of fresh water is added to 40 litres of tank water, so that the solution contains 2% salt. The value of x is

a) 40 b) 50 c) 55 d) 60

### Solution –

Percentage of water in current mixture = (100 – 5) = 95%

Percentage of water in output mixture = (100 – 2 ) = 98%