Answer:

Step-by-step explanation:
The total number of sums (not distinct) is
, because we're removing without replacement.
Count the sums that fit the stipulation (sum
5):
There are 8 sums that work. Therefore, the desired answer is 
For the trapezoid, the equation used to solve for the area is,
A = (0.5)(b₁ + b₂)(h)
where b₁ and b₂ are the measure of the bases and h is the height. Substituting the known values above,
1224 = (0.5)(70.5 + 65.5)(h)
h = 18
Thus, the height of the counter top is 18 inches.