If the total surface area of a sphere of radius r cm is equal to the total surface area of a cube of side s cm, which of the following is true?

The value of $${1.6×1.6×1.6−1.6×1.6×1.6}\over 1.6×1.6+1.6×1.6+1.6×1.6 $$ is

A company offers three types of successive discounts: (i) 25% and 15%, (ii) 30% and 10%, (iii) 35% and 5%. Which offer is the best for a customer?

The ratio of spirit and water in two mixtures of 20 litres and 36 litres is 3:7 and 7:5 respectively. Both the mixtures are mixed together. Now the ratio of the spirit and water in the new mixture is 

Given that ΔDEF ~ ΔABC. If the area of ΔABC is 9 cm² and area of ΔDEF is 12cm2 , BC = 2.1 cm, then the length of EF is:

Two pipe A and B can fill a tank in 16 hrs and 12 hrs respectively. The capacity of the tank is 240 litres. Both the pipes are opened simultaneously and closed after 2 hrs. How much more water (In Liters) needed to fill the tank?

Two boats, travelling at 5 Km/h and 10 Km/h respectively, head directly towards each other. They are now at a distance of 20 km from each other. How far apart are they (in Kms) one minute

before they collide? 

In a blue and yellow painting, blue and yellow are used in the ratio 4 : 3. If the ratio of blue and yellow in the upper part is 2 : 3, then in what ratio will the blue : yellow be in the lower part?