For the following questions answer them individually
Inside a triangle ABC, a straight line parallel to BC intersects AB and AC at the points P and Q, respectively. If AB = 6PB, then PQ ∶ BC is _________.
The heights of 48 students of a class are shown in the following table.
What is the percentage of students whose height is more than 160 cm?
The population of a village is 9,000. If the annual birth rate is 12.5% and the annual death rate is 2.5%, calculate the population after three years.
A man can row 5 km/h in still water. If the speed of the current is 2.5 km/h, it takes 4 hours more in upstream than in the downstream for the same distance. The distance is:
Simplify:
$$3p-\left[3p-\overline{p+q}-\left\{3p-\left(-\overline{q-p}\right)\right\}\right]$$
If base radius and height of a cylinder are 4 cm and 5 cm, respectively, then find the curved surface area of the cylinder [use $$\pi = 3.14$$].