Quantitative Aptitude - Arithmetic Ability Questions

In the given figure, PQR is an equilateral triangle with side as 12 cm. S and T are the mid points of the sides PQ and PR respectively. What is the area (in sq.cm) of the shaded region?

A school has 8 periods of 45 minutes each, every day. How long will each period be if the school has to have 9 periods everyday, assuming the working hours to be the same?

A number is decreased by 10% and the resulting number is again decreased by 20%. What is the final percentage of decrease?

The tops of two poles of height 60 metres and 35 metres are connected by a rope. If the rope makes an angle with the horizontal whose tangent is 5/9 metres, then what is the distance (in metres) between the two poles?

If Sec θ = 25/24 , then what is the value of Sin θ?

If 9x - [5(2x + 1)/2] = 9/2, then the value of x is?

Two numbers are 35% and 50% lesser than a third number. By how much percent is the second number to be enhanced to make it equal to the first number? 

How many times in a week does both the hands of the clock will coincide with each other?