Directions : In an Institution there are 800 students. Students use different modes of transport for going to the institution and return. The given pie diagram represents the requisite data. Study the diagram carefully and answer the questions.

The number of students who go to institute on foot is 

What should come in place of the question mark (?) in the following mathematical statement?
$${{?^6÷16=108}}$$

If two circles of radii 18 cm and 8 cm touch externally, then the length of a direct common tangent is:

Successive discounts of 10% and 10% are equivalent to a single discount of:

At what rate of simple interest will a sum of money double in 8 years?

AB and CD are two parallel chords of a circle lying on the opposite side of the centre and the distance between them is 17cm. The length of AB and CD are 10 cm and 24 cm, respectively. The radius (in cm) of the circle is

The table below gives the ranks secured by five different students in three different subjects in a qualifying examination:

Find the positive difference between the ranks secured by A in Physics and in Maths.

Given that x³ + y³ = 72 and xy = 6 with x > y. Then the value of (x – y) is