The ratio of speed of boat in still water to speed of stream is 8 : 1. It takes 4 hours by boat to cover 54 km in downstream & 42 km in upstream. Find the downstream speed of boat.

Kirti invested a sum of money at a certain rate of simple interest per annum for 3 years in "Bachat scheme". Had she invested the same sum in "Shiksha scheme" for 3 years which has a 2% higher simple interest rate per annum, the investment would have fetched ₹540 more. How much did Kirti invest?

On selling an article on certain price a shopkeeper gets a loss of x%. If he doubles the selling price he will get a profit of 30%. Find the value of x.

Vinit and Gopal can do a work together in 4 days. Shyam and Mohan can do the same work in 12 days. So, in how many days can all four complete that work together?

An amount of money appreciates to Rs. 7,000 after 4 years and to Rs. 10,000 after 8 years at a certain compound interest compounded annually. The initial amount of money was 

Direction (94-98): Study the following table to answer the given questions.
         Centre and Post-wise Numbered of candidate

In Kolkata, number of Specialist Officers is approximately what percent of that of Officers?

If a + b + c=15, abc=120 and (ab+bc+ca)=74, then the value of a³+b³+c³=?

The point Q(a, b ) is first reflected in y-axis to Q1 and Q1 is reflected in x-axis to (-5,3 ). The co-ordinates of point Q are