Question

For the bake sale, Helen made cookies and brownies. The cookies sold for 95 cents, and the brownies sold for 60 cents. If she baked 31 items that sold for $23.85, how many of each dessert did she sell?

Answer 1

Let us suppose that 'm' cookies and 'n' brownies were baked.

Since, Helen baked 31 items in total.

So, m+n = 31 (Equaion 1)

So, m = 31-n

Now, since cookies are sold for 95 cents, and the brownies sold for 60 cents.

Since, 1 $ = 100 cents

So, cookies are sold for $0.95, and the brownies sold for $0.60.

Helen sold the cookies and brownies at $23.85

So, 0.95m + 0.60n = 23.85 (Equaion 2)

Substituting the value of 'm' in equation 2, we get as

$0.95(31-n)+0.60n = 23.85$

29.45 - 0.95n +0.60n = 23.85

-0.35n = -5.6

So, n = 16

Since, m = 31-n

m = 31-16

m = 15

So, Helen sold  15 cookies and 16 brownies.