Sita deposited Rs . 5,000 at 10 % simple interest for 2 years. How much more money will Sita have in her account at the end of two years. If it is compounded semiannually. 

There are three bottles of mixture of syrup and water of ratio 2 : 3,  3 : 4,  7 : 5. 10 Litres of first and 21 Litres of second bottles are taken. How much quantity from third bottles is to be taken so that final mixture from three bottles will be of ratios 1 : 1. 

What approximate value should come in place of the question mark (?) in the following question? 
21.9714 × (8.8749 - 4.9393) = ?

If a : b =4 : 5, b: c=20 : 11 and c:d =6 : 7, then value of a : b : c : d will be

75 gm of sugar solution has 30 % sugar in it. Then the quantity of sugar that should be added to the solution to make the quantity of the sugar 70% in the solution is : 

Two trains 128 meters and 122 meters long are running towards each other on parallel lines at 48 kmph and 42 kmph respectively. In what time will they clear off each other from the moment they meet?