Question

A 12-ounce bottle of soda costs $3.60. If the unit price remains the same how much would a 20-ounce bottle of soda cost?

A) $3.00
B) $5.50
C) $6.00
D) $6.50

Answer 1

For this, simply set up a proportion. If 12 oz. costs $3.60, then this means $3.60 per oz, or
`(3.6)/(12)`. Now letś make a proportion for 20 oz. Itś asking for how much it would cost if the unit price was the same, which means that the two should have a similar ratio. Because we don´t know how much it costs yet, this means x dollars for a 20 oz. bottle, or
`(x)/(20)`. I´ve already mentioned that they two are proportional, so write
`(3.6)/(12) = (x)/(20)`.

To solve, cross multiply.

⇒
`12*x=3.6*20`

⇒
`12x=72`

Isolate variable x.

⇒
`(12x)/(12) = (72)/(12)`

⇒ x = 6: $6.00 for 20 ounces of soda.

Checking your work:

3.6/12 = 0.3

6/20 = 0.3

This means that theyŕe proportional, and that your answer is correct. Hope this was helpful.

Answer 2

Answer: D 6.50

Step-by-step explanation:

So if you were to do 3.60 x 2 it would be 7.2 but thats not the question so all you would have to do is think of it as 10 instead of 12 and well idk how to do It but its easy to find the answer without writing it down.