Geometry Questions

Multiple choice
  1. 36 square centimeters

  2. 45 square centimeters

  3. 48 square centimeters

  4. 64 square centimeters

  5. 72 square centimeters

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ratio of the areas of two similar triangles is the square of the ratio of their corresponding sides. Since the ratio of sides is 3:4, the ratio of areas is 3^2:4^2, which is 9:16. Given the smaller area is 27, the larger area is (27/9) * 16 = 3 * 16 = 48.

Multiple choice
  1. 90

  2. 120

  3. 150

  4. 200

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ratio of areas of similar triangles is the square of the ratio of their corresponding sides. Area ratio = (3/5)^2 = 9/25. Let A be the area of the larger triangle: 54 / A = 9 / 25. A = (54 * 25) / 9 = 6 * 25 = 150.

Multiple choice
  1. 5 centimeters

  2. 6 centimeters

  3. 7 centimeters

  4. 8 centimeters

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A tangent is perpendicular to the radius at the point of contact. This forms a right triangle with legs r and 12, and hypotenuse 13. By Pythagorean theorem, r^2 + 12^2 = 13^2, so r^2 + 144 = 169, r^2 = 25, r = 5.

Multiple choice
  1. 1 : 3

  2. 2 : 5

  3. 9 : 16

  4. 4 : 25

  5. a

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In a 6-8-10 triangle, the inradius r = (a+b-c)/2 = (6+8-10)/2 = 2. The circumradius R = hypotenuse/2 = 10/2 = 5. The ratio of areas is (pi*r^2) / (pi*R^2) = r^2 / R^2 = 2^2 / 5^2 = 4/25.

Multiple choice
  1. 25 cm

  2. 50 cm

  3. 55 cm

  4. 60 cm

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For two circles of equal radius r, the length of the direct common tangent AB is equal to the distance between centers d. The length of the indirect common tangent CD is sqrt(d^2 - (2r)^2). Given CD = 48 and r = 7, 48^2 = d^2 - 14^2. 2304 = d^2 - 196. d^2 = 2500. d = 50.

Multiple choice
  1. 518 cm2

  2. 520 cm2

  3. 616 cm2

  4. 224 cm2

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Radius = 14. Area of circle = (22/7)*14*14 = 616. The largest inscribed square has a diagonal equal to the diameter (28). Side of square s: s*sqrt(2) = 28, so s = 28/sqrt(2) = 14*sqrt(2). Area of square = s^2 = 196*2 = 392. Remaining area = 616 - 392 = 224.