Question

There are four blue marbles, an unknown number of red (r) marbles, and six yellow marbles in a bag. Which expression represents the probability of randomly selecting a blue marble, replacing it, and then randomly selecting a red marble

Answer 1

C is the answer :)

Explanation:

Took the test on edge2020

Answer 2

There are a total of 4 + r + 6 marbles in the bag

The probability of a blue is
`(4)/(10+r)`

The probability of a red is
`(r)/(10+r)`

The probability of choosing a blue, replacing it and then a red is

`(4)/(10+r)` ×
`(r)/(10+r)` = [tex]\frac{4r}{100+20r+ r^{2} /[tex]

Explanation: