The lengths of one side of a rhombus and one of the two diagonals are 6 cm each. Find the area of the rhombus (in cm²). 

There is 80% increase in amount in 5 years at simple interest. What will be the compound interest of Rs. 20,000 after 3 years at the same rate?

If 2sinθ+ 15 cos²θ=7, 0°˂θ˂90°, then what is the value of $$ {3-tanθ\over 2+tanθ}$$?

The ratio of milk and water in 42 litres of milk and water is 4 : 3. If x litres less of both quantities liquids be mixed up then their ratio becomes 7 : 5. Find the value of x.

If the sum and difference of two number are 20 and 8 respectively, then the difference of their squares is: 

A train of length 212 meter is running at 45 km/h. In what time (in seconds) will it cross a platform of length 188 meter?

In triangle PQR, points A, B and C are taken on PQ, PR and QR respectively such that QC = AC and CR = CB. If ∠QPR = 40°, then ∠ACB is equal to: 

A bag has Rs.420 in the denomination of Rs.1, Rs. 2 and Rs. 5 coins. The number Rs.1, Rs.2 and Rs.5 coins are in the ratio of 8: 1:5. How many coins of Rs.5 are in the bag?