Question
A box contains 20 red and 15 white balls. The
probability of drawing two balls of the same colour is?Solution
Let S be the sample space. Then, n(S) = number of ways of drawing 2 balls out of 35 = 35C2 = (35 x 34)/(2 x 1) = 595 Let E= event of drawing 2 balls of the same colour n(E) = 20C2 + 15C2 = (20 x 19)/(2 x 1) + (15 x 14)/(2 x 1) = 190 + 91 = 281 Therefore, P(E) = (n(E))/(n(S)) = 281/595 ` `
Find the difference between angle and its complement if the angle is three-seventh of its complement.
A triangular field has sides 13 m, 14 m, and 15 m. A well with a diameter of 7 m is dug outside the field. If the entire soil dug from the well is used ...
If O is circumcentre of acute angled triangle ABC, if ∠ OBC = 150 then ∠BAC = ?
Find the area of triangle having sides in the ratio 3:5:7 & the perimeter of the triangle is 60 cm
If I is the incentre of ΔABC , if ∠BAC = 300 , then what is the measure of ∠BIC?
At the centre of a circle of 20 cm radius, the angle made by an arc of 24(4/9) cm length is
Orthocenter of an right angle triangle lies on
Angles of a triangle are in the ratio 3 : 5 : 10. Find the sum of the smallest and middle angle of the triangle.
The diagonals of a rectangle are inclined to one side of the rectangle at 25°. The acute angle formed between the diagonals is:
