Suppose we have a bag with 10 slips of paper in it. Eight slips have a 3 on them and the other two have a 9 on them.
How many 's do we have to add to make the expected value equal to 6?
+2668 I will assume the question is supposed to be a 9.
We can write as equation:
3×8+9×2+9x=6(10+x)
42+9x=60+6x
18=3x
x=6
