Answer:
It approximately dropped 0.027777 per hour.
Step-by-step explanation:
First, we calculate the decrease.
Decrease = 11/40 = 0.275
Then, we calculate the time interval.
From 10 pm to 7:54 hours will be 9.54 hours
Time interval= (9 + 54/60) hours
Time interval=9.9 hours
Finally, we calculate how much it dropped each hour
0.275/9.9 ≈ 0.027777
So it approximately dropped 0.027777 per hour.
Expected value = Sum of Probability * Cost of each ice cream.
Expected value
= 50%* $1.20 + 30%* $2.00 + 2<span>0%* $3.50
</span>
= 0.50* $1.20 + 0.30* $2.00 + 0.2<span>0* $3.50
</span>
= $1.90
Expected value of the cost of one ice cream = $1.90