Q13 of 25 Page 15

A bag contains some red balls and some white balls. The probability of drawing a red ball is 1/4, and the total number of balls is 20. Find the number of red balls and white balls.

To Find: Number of red balls and number of white balls


Given: and total number of balls = 20


Concept Used:



Explanation:


Total Number of balls = 20


Let the number of red balls = x


Now,


Probability of drawing a red ball,




4x = 20



Hence, there are 5 red balls.


Now, number of white balls = Total balls – number of red balls


Number of white balls = 20 – 5 = 15


Hence, the number of white balls are 15.


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