By Selling 90 pens for Rs. 80 a man loses 20%. What should be the selling price (in Rs.) of 90 pens for 20% profit?

Excluding stoppages, the speed of a bus is 80 kmph and including stoppages, it is 60 kmph. For how many minutes does the bus stop per hour?

The cost price of 60 articles is same as the selling price of x articles. If there is a profit of 20%, then what is the value of x?

In how many different ways can the letters of the word ‘CREAM’ be arranged?

Two poles of equal height are standing opposite to each other on either side of a road, which is 28 metre wide. From a point between them on the road, the angle of elevation  of the top are 30° and 60°. The height of each pole is:-

If a manufacturer gains 10 percent, wholesaler 15 percent and retailer 25 percent, then the production cost of an article, whose retail price is Rs. 1,265, is 

Find the value of given expression.

3 – (– 6) {– 2 – 9 – 3} ÷ 7{1 + (– 2) (– 1)}

An alloy contains a mixture of two metals X and Y in the ratio of 2 : 3. The second alloy contains a mixture of the same metals, X and Y. in the ratio 7 : 3. In what ratio should the first and the second alloys be mixed so as to make a new alloy containing 50% of metal X?