Among 80 students at a collage, 20 take Mathematics, 30 take English, and 12 take both Mathematics and English. Find the number of the students who take (a) Mathematics or English, (b) neither Mathematics nor English.
The price of 3 horses is same as the cost of 5 cows. If total cost of 4 horses and 6 cows is Tk 1900, find the cost of one horse.
A square and an equilateral triangle have equal perimeters. If the diagonal of the square is 12√2 cm, then what is the area of the triangle?