A dishonest grocer sells rice at a profit of 10% and uses weights which are 20% less than the marked weight. The total gain earned by him will be

If \(tan\theta = {a \over b}\), then \({a.sin\theta + b.cos\theta \over {a.sin\theta - b.cos\theta}}\) is:

A is twice as good a workman as B and together they finish a piece of work in 13 days. In how many days will B alone finish the work?

Anu can complete a piece of work in 22 days. Shama is 60% more efficient than Anu. How many days does Shama alone take to complete the same piece of work?