
Explanation:
Since we have given that
The prices of three t-shirts styles i.e $24, $30, $36 with their probability is given by

As we know that,


Now,

and

So,

So, the expected value of a t-shirt = $31.
Separating the balloons into five equal groups
<span>⊙⊙⊙ ___ ⊙⊙⊙ ___ ⊙⊙⊙ ___ ⊙⊙⊙ ___ ⊙⊙⊙ </span>
<span>each group (fifth) has three balloons ___ four-fifths is twelve</span>
A = 10
Step by step
3+7=10
10+(-7)=3
<span>(-3 + 3i) + (-6 + 6i) =
= -3 + 3i + (-6) + 6i
= 3i + 6i + (-3) + (-6)
= 9i + (-9)
= 9i - 9
</span>