Jambmaths question:
A box contains 5blue balls, 3 red balls and 2 white balls. Two balls were selected from the box with replacement. Find the probability of obtaining two blue or two red balls
Option A:
$\tfrac{3}{250}$
Option B:
$\tfrac{1}{50}$
Option C:
$\tfrac{17}{50}$
Option D:
$\tfrac{3}{25}$
Jamb Maths Solution:
Total number of balls = 5 + 3 + 2 = 10Prob. Of 2 blue balls = $\tfrac{5}{10}\times \tfrac{5}{10}=\tfrac{25}{100}=\tfrac{1}{4}$Prob. Of 2 red balls = $\tfrac{3}{10}\times \tfrac{3}{10}=\tfrac{9}{100}$Prob. Of 2 blue or two red ball = $\tfrac{1}{4}+\tfrac{9}{100}=\tfrac{25+9}{100}=\tfrac{34}{100}=\tfrac{17}{50}$
Jamb Maths Topic:
Year of Exam: