(A) 81
(B) 159
(C) 166
(D) 285
(E) 324
2. A merchant paid $300 for a shipment of x identical calculators. The merchant used 2 of the calculators as demonstrators and sold each of the others for $5 more than the average (arithmetic mean) cost of the x calculators. If the total revenue from the sale of the calculators was $120 more than the cost of the shipment, how many calculators were in the shipment?
(A) 24
(B) 25
(C) 26
(D) 28
(E) 30
3. If a 3-digit integer is selected at random from the integers 100 through 199, inclusive, what is the probability that the first digit and the last digit of the integer are each equal to one more than the middle digit?
(A) 2/225
(B) 1/111
(C) 1/110
(D) 1/100
(E) 1/150
I need to know the steps in details. Can anyone help
![Confused :?](./images/smilies/confused.png)