Question

If two rulers are chosen randomly one at a time from the box, without replacing the first one, what is the theoretical probability that both rulers are yellow? 1/25
Red 5
Blue 2
Green 4
Yellow 4
Orange 5
*1/5 x 1/5 =1/25 ?

Answer 1

Let us start by counting the total number of rulers - 5 + 2 + 4 + 4 + 5 = 20
P(1st time yellow) = 4/20 = 1/5
Now that we won't replace, then it's one less from both the numerator AND denominator.
P(2nd time yellow) = 3/19


\(\Large \color{MidnightBlue}{\Rightarrow {1 \over 5} * {3 \over 19} = {3 \over 95} }\)

Answer 2

well no shame in trying thanks

Answer 3

Absolutely lol