The area is the area of 2 pairs of congruent triangles and one rectangle. Use the formulas for the areas of these figures, then add results.
Front triangle area (A = (1/2)bh)
.. = (1/2)(16 m)*(25 m) = 200 m^2
Right side triangle
.. = (1/2)(22 m)*(24 m) = 264 m^2
Base (A = lw)
.. = (16 m)*(22 m) = 352 m^2
Total area
.. 2*front triangle +2*side triangle +base
.. = 2*200 m^2 +2*264 m^2 +352 m^2
.. = 1280 m^2
To get the x-intercepts of the function, f(x) = 4x2 – 24x + 20
It has to be equated to zero and the values of x are the x-intercepts. So,
4x2 – 24x + 20 = 0
The resulting equation is a quadratic equation which can be solved by different methods. The solution is
x = 5, 1
The average therefore is:
(1+5/)2 = 3
You made a mistake with the probability 
, which should be 
in the last expression, so to be clear I will state the expression again.
So we want to solve the following:
Conditioned on this event, show that the probability that her paper is in drawer 
, is given by:
(1) 
and
(2) 
so we can say:
is the event that you search drawer 
and find nothing,
is the event that you search drawer and find the paper,
is the event that the paper is in drawer 
this gives us:
Solution to Part (1):
if 
, then 
,
this means that
as needed so part one is solved.
Solution to Part(2):
so we have now that if = , we get that:
remember that:
this implies that:
so we just need to combine the above relations to get:
as needed so part two is solved.
I think the answer is (C)
