The two cereal boxes shown have corresponding edges

in a ratio of 2 : 3. If the smaller box sells for $2.50 and
the larger box for $4.00, which is the better buy? Why?
What assumption(s) do you have to make when solving
the problem? Estimate, then check.

2 answers

It's not the size of the box that makes a better buy, it is the quantity and quality of the contents.

Are all edges of the boxes the same ratio or only one edge?

2/3 = .67

$2.50/$4.00 = .625

I hope this helps. Thanks for asking.
I think the assumption we were supposed to make that the volume of two similar solids is proportional to the cubes of their sides.

the ratio of their sides is 2:3
so the ratio of their cubes is 8:27

So if they were priced by the same unit price, the larger should cost 27/8($2.50)
= $8.44

but the larger only costs $4.00, so buyer the larger box is definitely a much better deal.