Answer:
Original Price = 160
Sale Price =40
Step-by-step explanation:
Let Original Price be x and Sale Price be y
y=1/4 of x (Equation 1)
x=120+y (Equation 2)
Put value of x from equation 2 in equation 1
y= (1/4)*(120+y)
y=120/4 + y/4
y-y/4=30
3y/4=30
y=30*4/3
y=40
Put value of y in Equation 2
x=120+40
x=160
Answer: See below
Step-by-step explanation:




Simplify:

Use a calculator................
Answer:
Step-by-step explanation:
simple:
2900(1+.13*30)=14210
Compounding

We have a bunch of rectangles making up the lateral sides of this figure. They have side length 12 and height 13.
So the area of one rectangle is 12 x 13 = 156.
We have 6 of these rectangles, so our lateral area is 6(156) = 936.
The total surface area requires that we include the area of the base. To find the area of a regular polygon we take half of the product of the apothem and perimeter.
A = (1/2)*a*p
The apothem is given to be 10.39,
and the perimeter is fairly easy to calculate:
With the side length being 12, the perimeter is then 6(12) = 72.
So then the area of our base is (1/2)*10.39*72 = 374.04
So then the total surface area is the (base area) + (lateral area),
374.04 + 936 = 1310.04