Question

A bag contains 20 balls Bandw If one ball Bound w ifone ball drawn@round and probility of white ball is 2/5Hence fixed explain step by step​

Answer 1

Answer:

5

Step-by-step explanation:

Probability of black balls =  

20

x

​

 

Probability of black balls after adding 10 new balls =  

30

x+10

​

 

According to the question

=  

30

x+10

​

=  

20

2x

​

 

20x+200=60x

⇒40x=200⇒x=5