Question

Amy buys 4 cans of soup at the store for a total of $5.00. Which equation represents the cost y, in dollars, of buying x cans of soup given that the cost is proportional to the number of cans of soup?

Answer 1

`y=1.25x`

Explanation:

If `y` is the cost (in dollars) of buying `x` cans of soup
and the relation is a direct proportion then:
`color(white)("XXX")y=k * x` for some constant `k`

We are told that `y=5.00` when `x=4`
So
`color(white)("XXX")5.00=k * 4`

`color(white)("XXX")k= (5.00)/4=1.25`