Mathematics

A pipe can fill up an empty tank in 15 minutes. Another pipe flows out 20 liter of water per minute. If the two pipes are opened together and the empty tank is filled in 135 minutes, how much water does the tank contain?

Mathematices

In a square field of side 30 meters, 4 cows are grazing the field as they are tied at each of the four corners with a 14 meter long rope for each cow. What is the ungrazed area in the field?

Mathematices

There are two examination rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A then the number of students in A is double the number of students in B. What is the number of students in room A?

Mathematices

If m and n are whole numbers such that $m^n$ prime prime =121, then the value of (m - 1)^{(n + 1)}  is:

Mathematics

A brother and a sister share out their collection of 5,000 stamps in the ratio of 5 : 3. The brother then shares his stamps with two friends in the ratio of 3 : 1 : 1 keeping most for himself. How many stamps does each of his friends receive?

Mathematics

If the length of the two sides of a trapezoid are 4cm and 7cm and height of the trapezoid is 7cm, calculate the area of the trapezoid.