Question

Brenda and Jasmine are selling cookie dough for a school fundraiser. Customers can buy packages of chocolate chip cookie dough and packages of double chocolate cookie dough. Brenda sold 6 packages of chocolate chip cookie dough and 4 packages of double chocolate cookie dough for a total of $86. Jasmine sold 3 packages of chocolate chip cookie dough and 5 packages of double chocolate cookie dough for a total of $85. What is the cost each of one package of chocolate chip cookie dough and one package of double chocolate cookie dough?

Answer 1

one package = $5. / double package= $14

Explanation:

Lets say x is a package and y a double package

6x + 4y = $86

2(3x + 5y = $85)

6x + 10y = $170

-6x -4y. -86

6y = $ 84

÷6. ÷6

y= $14

6x +4y = $86

6x + 4($14) = $86

6x + $56 = $86

-56. -56

6x = $30

÷6. ÷6

x = $5

Answer 2

chocolate chip = 5

double chocolate chip=14

Explanation:

c = chocolate chip

d = double chocolate chip

Brenda

6c+4d = 86

Jasmine

3c+ 5d = 85

Multiply the second equation by -2

-6c -10d = -170

Add this to the first equation

-6c -10d = -170

6c+4d = 86

--------------------

- 6d = -84

Divide by -6

-6d /-6 = -84/-6

d =14

Now we can find c

3c+ 5d = 85

3c+5*14 = 85

3c +70 = 85

Subtract 70

3c = 85-70

3c = 15

Divide by 3

3c/3 = 15/3

c = 5