12 years old probability ..

[Lucasz]

a farmer has 4 white 6 black and 20 brown cows in a shed that need to be milked
What is the probability the first cię through the hate will be NOT Black

i thought is 24/30 =4/5
But was told this is incorrect.

could anyone provide me with correct answer Please .

 

[Dr.Peterson]

I presume that's "the first cow through the gate".

There are 24 non-black cows out of 30, so your answer is clearly correct.

How were you told you were wrong? Was this a human or a computer? And did you quote the complete and exact wording of the problem? If not, there might be some detail that makes your answer unacceptable, e.g. if they required a decimal or percentage answer.

 

[Lucasz]

Yes it is first cow.
And it was a teacher who told me that.
Due to cov19 we are not allow back to school
Still waiting for her reply .
Many thanks for your help