Answer:
A)
Important information:
The total cost includes the price of 2 tickets and the price of yogurt.
The total cost: 19.90$
The price of yogurt: 5.5
The price of 2 tickets: unknown
Each of the tickets costs the same amount of money.
Verbal Description:
For the unknown value, the letter x is often selected to represent this unknown value.
Here, we select x that is the price of 1 ticket, then the price of 2 tickets would be 2x.
=> We have the equation: 2x + 5.5 = 19.90
Transfer 5.5 to the right, and then divide both sides by 2, we have:
(2x)/2 = (19.9 - 5.5)/2
Take the simplification, we have:
x = 7.2$ (this is the price of a ticket)
B)
Use the same strategy as shown in A), we have:
Total number of stamps: 100
Mari's number of stamps: x
Carlos's number of stamps: x + 5
Amanda's number of stamps: 3x
=> 3x + x + x + 5 = 100
=> 5x = 100 - 5
=> 5x = 95
=> x = 19
Mari's number of stamps: 19
Carlos's number of stamps: 19 + 5 = 24
Amanda's number of stamps: 3 x 19 = 57
C)
The perimeter of the garden:
perimeter = (width + length) x 2
perimeter = 256
width = w
length = w + 8
=> We have:
256 = (w + w + 8) x 2
<=>256 = (2w + 8) x 2
<=> 256/2 = (2w + 8) x 2/2
<=> 128 = 2w + 8
<=> 128 - 8 = 2w
<=> 120 = 2w
<=> w = 60
=> width of garden: 60
=> length of garden: 60 + 8 = 68