Question

I have 2 questions that i need help on, please help! Thank you and God bless you.
1. A shoebox holds a number of disks of the same size. There are 5 red, 6 white, and 7 blue disks. You pick out a disk, record its color, and return it to the box. If you repeat this process 250 times, how many times can you except to pick either a red or white disk?
2. Each student in a class of 25 students in a class of 25 students wrote down a random digit. What is the predicted number of students who wrote a digit greater than 7?

Answer 1

You have 18 discs in the box of which 11 are red or white,
so the prob(red or white) = 11/18

Since you are returning the disc, that prob remains the same
So in 250 turns, how many times do you think your event will happen ?

2nd, not enough data. There are an infinite number of numbers greater than 7
Was there a restriction on the numbers they could pick?

Answer 2

there are only two digits greater than 7 -- 8 and 9
so, I'd expect 2/10 of the students to have chosen one of them.