A cyclist rides 20 km in 120 minutes and rides another 25 km in 150 minutes. What is the average speed of the cyclist, in km/h?

If $(x + {1\over x}) = \sqrt6 $, and x > 1, what is the value of $(x^8 - {1 \over x^8}) $?

A father gives 8% of his monthly income to both his sons as pocket money. The elder son gets 85% of the total amount given to both sons. He spends 90% of the amount and saves Rs. 17. What is the monthly income of his father?

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

The bar-chart shows the production of maize by a state (in 1000 tonnes) over the years.

What was the percentage increase in the production of maize in 2019 compared to that in 2017?