Simplify the following expression.

 25-(4÷2)+11.5+9.5

Select the number that will come in place of the question mark (?) in the following mathematical statement.

$${5\over 9} \ of \ {11\over 14}\ 42\% \ of \ 540=?^2 -45 $$

A train running at the speed of $${140\over 9} $$  m/sec, crosses a pole in 27 sec. Find the length of the train.

Study the given pie-chart and answer the question that follows.

The pie-chart shows the percentage distribution of the number of different types of chocolates distributed by Akanksha to the residents of a children's home, as percentages of all the chocolates taken together, that were distributed by her to these residents.

The average number of chocolates of Dairy Milk, 5-Star and Snickers taken together is equal to the number of chocolates distributed of which of the given types?

The following bar graph shows the number of students who like four different colours.

Akshay has 30 articles, each having the same cost price. He marked the price of each article at 30% above its cost price. He sold 15 of the articles at a discount of 20% each, and the remaining 15 articles at a discount of 10% each, thereby gaining a total profit of ₹630. What was the cost price of each article?

The length, the breadth, and the height of a cuboid are 40 cm, 20 cm and 10 cm. respectively. What is the volume of this cuboid?

80 liters of a mixture of alcohol and water contains 60% alcohol. If 'X' liters of water is added to this mixture, then the percentage of alcohol in the new mixture becomes 40%. What is the value of 'X'?