The answer to the question is 5 -5
40 x 60 x 98 x 97
There are 40 seniors to be president, 60 juniors to be juniors, 98 people are left since 2 were elected for president and vice president. After the Secretary has been elected, there are 97 people left. SImply multiply the numbers. There are 22,814,400 ways.
Material=wall+2*side and material is 40 ft so:
40=w+2s
w=40-2s
Area=ws, using w from above we get:
A=(40-2s)s
A=40s-2s^2
dA/ds=40-4s and d2A/ds2=-4
Since d2A/ds2 is a constant negative acceleration, when dA/ds=0, A(s) is at an absolute maximum.
dA/ds=0 when 4s=40, s=10 ft
And since w=40-2s, w=20 ft
So the dimensions of the pen are 20 ft by 10 ft, with the 20 ft side being opposite the wall. And the maximum possible area is thus 200 ft^2
