Question

A bag has 2 yellow, 7 red, and 1 green marble. What is the probability of picking a red marble, replacing it, and then picking a green marble?

Answer 1

probability red+green

first pick(red) : 7/10
2nd pick( green) : 1/10

the answer maybe like this
prob : 7/10+1/10 = 8/10 =4/5