Answer:
0, because the house is already painted. If this isn't a riddle then, it should take 4 days because that is half the people, two times the workload per person.
Given:
The sum of two terms of GP is 6 and that of first four terms is 
To find:
The sum of first six terms.
Solution:
We have,


Sum of first n terms of a GP is
...(i)
Putting n=2, we get


...(ii)
Putting n=4, we get



(Using (ii))
Divide both sides by 6.
Taking square root on both sides, we get

Case 1: If r is positive, then using (ii) we get
The sum of first 6 terms is




Case 2: If r is negative, then using (ii) we get
The sum of first 6 terms is




Therefore, the sum of the first six terms is 7.875.
I think the answer may be C
Answer: A cardboard box without a lid is to have a volume of 32,000 cubic cm. Find the dimensions that minimize the amount of cardboard used
. ans: base 40 x 40, height = 20
Solution:
The typical box might look like the one below
where . In addition we have xyz = 32000 ,so we need to minimize .
We have,
From the geometry of the problem so y = x. So or x = 40.
Finally, y = x = 40 and z = 32000/(xy)=20.