Quantitative Aptitude - Arithmetic Ability Questions

2cos[(C+D)/2]sin[(C-D)/2] is equal to

Select the odd word/letters/number/number pair from the given alternatives.

In a mixture of milk and water, there is 19% milk. If the quantity of milk in the mixture is 437 mililitres, then what is the total quantity (in millilitres) of mixture?

The average marks in science subject of a class of 20 students is 68. If the marks of two students were misread as 48 and 65 of the actual marks 72 and 61 respectively, then what would be the correct average?

Three years ago, the average age of a family of 5 members was 17 years. A baby having been born, the average age of the family is the same today. The present age of the baby is

50 litre mixture of water and alcohol contains 10% alcohol. How much more alcohol must be added to make the strength of alcohol 40% in the new mixture?

In a container, two types of liquids P and Q are in the ratio of 3 : 7. If 10 litres mixture is drawn off from the container and filled with 6 litres of liquid Q,then the ratio of P and Q becomes 1 : 3. What was the original quantity (in litres) of mixture?

Meghnad can do a piece of work in 45 hours. If he is joined by Jayshri, who is 50% more efficient, in what time will they together finish the work?