Ineed serious anyone knows how too do this

You could do this:

+++=2

This would simplify down to,

-1 + 1 + 1 +1 = 2

The -1 and 1 would cancel out giving you,

1 + 1 = 2

2 = 2

Expected value, Ex = $46

Step-by-step explanation:

X ($) : 350       300     150

P(X) : 0.02       0.06    0.14

Expected value, Ex = Σx*p(x)

                                = $350*0.02 + $300*0.06 + $150*0.14

                                = $7 +$ 18 + $21

                                = $46

Therefore, Expected value, Ex = $46