Im confused please help!?

Question

Can someone please explain these to me??? I'm really confused, Thanks!!!

1~ Which "box of cereal" costs the least per ounce?
Weight (oz) Cost
12 $2.50
18 $3.69
24 $4.95

2~ Solve the proportion: w over 8 = 1/3

3~ A truck is 26 feet long. Find the length on a scale model if 1 inch represents 5 1/2 ft.

(BTW, i don't necessarily want you to do it for me, just explain the best you can for how to do them... please and thankyou)~
:-)

Answer 1

I believe the first answerer's answers to #1 and 3 are incorrect.

1. You must have the answer in cost per ounce. Therefore, divide the cost of each by ( not into) the weight of each:
$2.50/12 = $0.208330 or $0.21 when rounded to cents
$3.69/18 = $0.205000 or $0.21 when rounded to cents
$4.95/25 = $0.205625 or $0.21 when rounded to cents

2. Write the equation as (w/8) = (1/3) (without parentheses)
Then, multiply both sides by 8, getting:
w = 8/3 or 2 2/3 or 2.666667

3. divide 26 feet by (not into) 5.5 feet
26/5.5 = therefore the scale is: 4.7272 ft to 1 inch

Answer 2

1. You need to divide the cost into the weight of the cereal, which even comes out the least would be correct.

2. Solve for w by multiplying by 8 on both sides. w=8*1/3

3. How many inches are in 26 ft. Then divide that inot 5.5 ft.