Question

A box as 20 ball of which x are red when 4 more red ball add then ball is is picked up the probability 1/2 then value of x ​

Answer 1

P(red ball)=

x+4/20=1/2

or x=6

Answer 2

P(red ball initially) =x/20

P(red ball after adding 4 more ) = x+4/20
Which is 1/2
So 1/2 *20 = x+4
So 10=x+4
10-4 =x
6 =x
Or
x=6