There is 10% loss if an article is sold at Rs. 270. Then the cost price of the article is

If (a+b) : (b+c) : (c+a) = 7 :6 : 5 and (a+b+c)=27, then what will be the value of $$ {1\over b}:{1\over a}:{1\over c}$$.

The numerator of a fraction is 4 less than its denominator. If the numerator is decreased by 2 and the denominator is increased by 1, the denominator becomes eight times the numerator. Find the fraction? 

The two trains cross each other in 12 seconds, moving in the opposite direction, and they take 60 seconds to travel in the same direction. both trains can have speed in (m/sec).

When the price of an audio system was reduced by 20%, the sale increased by 80%. What was the net effect on the sale?

If a=2b/3, b=2c/3, and c=2d/3, then find the ratio of b and d:

Find the difference between mean and median in the given data 2.5, 4.6, 7.2, 3.3, 4.9, 5.6, 2.7?

Which of the following is the largest fraction   $${6\over7},{5\over6},{7\over8},{4\over5} ?$$