If a shopkeeper bought 70 kg of potatoes for Rs 420 and sold the entire purchase at the rate of 6.50 per kg, what was his profit percentage?

The cost price of an article is ₹390. If it is to be sold at a profit of 3.12 %, how much would be its approximate selling price?

Simplification the following equations shown below

A travels 20 km with a speed of 40 km/hr. He travels another 45 km with a speed of 15 km/hr. what is his average speed for the entire journey?

The monthly income of two persons are in the ratio 2 : 3 and their monthly expenses are in the ratio 5 : 9. If each of them saves ₹600 per month, then their monthly incomes are 

If x+y=10 and xy=4, then what is the value of x⁴+y⁴=?

The average of three consecutive odd numbers is 12 more than one third of the first of these numbers. What is the last of the three numbers?

An Aeroplan flying horizontally at a height of 3 km. Above the ground is observed at a certain point on earth to subtend an angle of 60 °. After 15 sec flight, its angle of elevation is changed to 30 °. The speed of the Aeroplan (taking √3 = 1.732)