A bag contains 21 red marbles, 4 white marbles, and 3 gray marbles. Do you randomly pick out a marble recorded color and put it back in the bag. You repeat this process 84 times. How many white or gray marbles do you expect to get?

28

Step-by-step explanation:

you add 21, 4, and 3 to find the total

then you find how many are white or gray

7/28= 1/3

1/3 times 84

84 times 1 divided by 3

84/3

38.5

step-by-step explanation:

lets say, first number = r

second number = 3r+7

total = 49

(r)+(3r+7)= 49

4r+7 = 49

4r = 42

r = 42/4

r= 10.5

3r+7 = 3(10.5)+7 = 38.5

hope this