A speedboat whose speed is 15 kmph in still water goes 30 kmph downstream and comes back in a total of 4hrs 30min. What is the speed of the stream in kmph?

A sphere of 10.5 cm radius is melted. It is then casted into a cuboid of maximum volume. What will be the total surface area of such cuboid?

A sum of money becomes 2.5 times itself at 12.5% simple interest p.a. What should be the period of investment to get this much return?

A tiffin box manufacturer reduces the price of his school kids' tiffin from Rs.30/- to Rs.28/- per tiffin and the price of regular tiffin from Rs.24/- to Rs.23/- per tiffin. A caterer normally spends Rs.1440/- a month for tiffin and 3/4 of this is for regular tiffin. How much will they save a month under the new prices?

A triangle has sides of lengths 10, 24 and k. k is a positive integer. The number of values of k for which this triangle has three acute angles is

Calculate the area of the triangle in square cm if a right angled triangle where the length of the shorter leg is one third of the length of its hypotenuse. And the length of the shorter leg is 7 cm.

During a given week an author spends 1/4 of his time preparing first drafts, 3/8 of his time editing the drafts and the rest of the time in preparing final drafts. If he works 48 hours during the week, how many hours did he spend in preparing final drafts?

Find the speed of the boat in still water if the river runs at 4 km/hr. The time taken by a Suresh to row the boat upstream is 3 as the time taken by him to row it downstream.

From its total income, an IT company spent Rs.20, 000 for marketing, half of the remainder on operations and had Rs.6000 left. What is the total income of the company?

Gaurav buys milk at Rs. 60 per litre, adds water to it and then sells it at Rs. 75 per litre. What should be the ratio of milk to water to get a profit of 37.5%?

If 12 box containers require 18 feet of wall space, how many feet of wall space will 30 box containers require?

If Dev walks 30 miles/hr. he reaches 1 hour before and if he walks with a speed of 20 miles/hr. he reach 1 hour late. Find the distance between 2 points and the exact time of reaching destination is 11 am then find the speed with which he walks.

If a bank clerk can process 80 drafts in half an hour, how many drafts can she process in seven and half hour day?

In a certain college, 20% of the boys and 40% of the girls attended the annual college outing. If 35% of all the students are boys, what percent of all the employees went to the outing?

In a typical motor cycle rally, every motor cycle has to reach a speed of 20 m/min within a minute and it increase its speed by 20 m/min and the sum was 1600 m/min. Four minutes later, a new motor cyclist started running in the race. After another two minutes, the motor cyclist with the speed of 400 m/min stopped due to injuries and again two new motor cyclist started running in the race. What is the current average speed?