Question

Jane and Beth are selling cupcakes and cakes to make money. They sell the cupcakes for $3 and cakes for $12.

In order for Jane and Beth to make at least $300, what is the minimum number of cakes they must sell if they only sell 25 cupcakes?

Answer 1

So 25 cupcakes is 25x$3= $75 now she needs to sell 300-75= $225 worth of cakes... so 225/12= 18.75 or rounding up 19 cakes

Answer 2

25

Explanation:

Let x be the no. of cupcakes and y be the number of cakes

We are given that they only sell 25 cupcakes

So, equation becomes :
`x+y=25` ---A

Cost of 1 cupcake = $3

Cost of x cupcakes = 3x

Cost of 1 cake = $12

Cost of y cakes = 12y

We are given that Jane and Beth to make at least $300

So,
`3x+12y\geq 300`---B

Substitute the value of x from A in B

`3(25-y)+12y\geq 300`

`75-3y+12y\geq 300`

`75+9y\geq 300`

`9y\geq 300-75`

`9y\geq 225`

`y\geq (225)/(9)`

`y\geq 25`

Hence the minimum number of cakes they must sell if they only sell 25 cupcakes is 25