class 9th maths chapter 9 exercise 9.1 – Circles (Class 9) Exercise 9.1 Solutions (Class 9) Circles 1. Recall that two circles are congruent if they have the same radii. Prove that equal chords of congruent circles subtend equal angles at their centres. Given: Two congruent circles with centres O and O’. They have equal … Read more

heron’s formula class 9 extra questions(R.D. Sharma Level – Class 9) Extra Practice Questions Heron’s Formula (R.D. Sharma Level – Class 9) 1. The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3:2. Find the area of the triangle. Let the equal sides be 3x … Read more

Exercise 10.1 class 9th – Heron’s Formula (Class 9) Exercise 10.1 Solutions (Class 9) Heron’s Formula 1. A traffic signal board, indicating ‘SCHOOL AHEAD’, is an equilateral triangle with side ‘a’. Find the area of the signal board, using Heron’s formula. If its perimeter is 180 cm, what will be the area of the signal … Read more

surface area and volume class 9 extra questions (R.D. Sharma Level – Class 9) Extra Practice Questions Surface Areas and Volumes (R.D. Sharma Level – Class 9) 1. The curved surface area of a right circular cone is 12320 cm². If the radius of its base is 56 cm, find its height. (Use π = … Read more

exercise 11.4 class 9th – Surface Areas and Volumes (Class 9) Exercise 11.4 Solutions (Class 9) Surface Areas and Volumes (Assume π = 22/7, unless stated otherwise) 1. Find the volume of a sphere whose radius is: Formula: Volume of a sphere = (4/3)πr³ (i) 7 cm Volume = (4/3) × (22/7) × 7³ = … Read more

class 9th exercise 12.1 – Statistics (Class 9) Exercise 12.1 Solutions (Class 9) Statistics 1. A survey conducted by an organisation for the cause of illness and death among the women between the ages 15 – 44 (in years) worldwide, found the following figures (in %): Causes Female fatality rate (%) Reproductive health conditions 31.8 … Read more