Answer:
63/10
Step-by-step explanation:
Use present value equation.
If present value of annuity equals 400,000, then you are indifferent.

where v = 1/(1+r) and A = annual payment = 800,000/20 = 40,000
PV = 400,000
After subbing in the numbers, the equation is:

Therefore at interest rate of about 7.75% you are indifferent.
So it can now be bought for 65% of its regular price.
That's a good deal. If I needed a clearance rack, I'd buy it.
78 / 3 3/4 =
78/1 / 15/4 =
78/1 x 4 /15 = 312/15 = 20.8
20 pieces 3 3/4 inches long can be cut