Among a set of 4 black balls and 3 white balls, how many selections of 3 balls can be made such that at least 2 of them are black balls?
Selecting at least 2 black balls from a set of 4 black balls in total selection of 3 balls can be 2 black and 1 white balls 3 black and 0 white balls Therefore, our solution expression looks 4C2 × 3C1 + 4C3 × 3C0 6 X 3 + 4 X 1 = 18 + 4 = 22 ways
The lengths of three medians in a triangles are 21 cm, 28 cm, 35 cm. What is the area of that traingle (in cm 2 )?
Find the radius of the sphere whose volume is 562.5π cm3
ABCD is a square. P, Q, R and S are points on the sides AB, BC, CD and DA respectively such that AP = BQ = CR = DS. Angle SPQ equal to ?
The area of the largest triangle inscribed in a semi-circle of radius R is-
A circular clock has the hour hand of length 42 cm. Find the length of the distance it covers by its tip from 11 p.m. to 3 a.m.
In the given figure. ABCDEF is a regular hexagon whose side is 6 cm. APF, QAB, DCR and DES are equilateral triangles. What is the area (in cm2
In ∆ABC , G is the centroid , AB = 5 cm, BC= 6 cm and AC = 7 cm , find GD, where D is the mid-point of BC?
ABC is an isosceles triangle inscribed in a circle. If AB = AC = 12√5 and BC = 24 cm then radius of circle is
