If 16 : X :: X: 196, find the positive value of x?

Rachit invests ₹12,000 for a 2-year period at a certain rate of simple interest per annum. Prasad invests ₹12,000 for a 2- year period at the same rate of interest per annum as Rachit, but in Prasad's case the interest is compounded annually. Find the rate of interest per annum if Prasad receives ₹172.80 more as interest than Rachit at the end of the 2-year period. 

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.

The selling prices of two articles are equal. If the first article is sold at a profit of 20% and the second article is sold at a loss of 20%, what will be the overall loss percentage?

The following pie chart shows the sectors representing the shares of the number of electric buses manufactured in each of 7 different colours in a given year in terms of the central angles (in degrees) with respect to the total number of buses manufactured during that year of all the 7 colours taken together.

What is the difference in the percentage shares of buses of C4 and C6? [Give your answer correct to 2 decimal places.]

The bar chart given below shows the exports (in ₹000) and imports (in ₹000) of a country for 5 consecutive years.

What is the positive difference in the total export figures of all the five years taken together and the total import figures of all the five years taken together?

A train moves at a speed of 35 km/h for the first 2 hours and at a speed of 50 km/h for the next 4 hours. Find the average speed of the train during the entire journey.

The base of a triangle is 16 cm and its area is $${144cm^2}$$. Find its corresponding height, with respect to the given base.