Cans of soda at a local store a six-pack of soda costs $2.59 and indivdual cans cost $0.80. What is the maximum of cans of soda that can be purchased for $15​

 30 cans (buy them by the six-pack; so you'd buy 5 six-packs)

Explanation:

Let's say you buy six-packs only. Divide the amount of money you have over the cost per six-pack.

15/(2.59) = 5.7915 which rounds down to 5.

If you buy six-packs only, then you can buy a max of 5 of them. That gets you 5*6 = 30 cans of soda.

Now let's say you buy individual cans only. We'll use the same idea mentioned earlier but this time divide over 0.80

15/(0.80) = 18.75 which rounds down to 18

We round down because we can't buy that 19th can of soda (note how 19*0.80 = 15.2 which is larger than 15).

So if you buy individual cans only, then you can get a max of 18 cans.

We see that it's better to go with the six-pack option (in the first section) since we can get 30 cans compared to 18 cans.

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