Question

Christine received a
$90
gift card for a coffee store. She used it in buying some coffee that cost
$8.44
per pound. After buying the coffee, she had
$64.68
left on her card. How many pounds of coffee did she buy?

Answer 1

From what we are given, this represents a linear system because there is a fixed amount (90) and a variable (8.44). We can define variables and create an equation.

Let x represent the number of coffee pounds
Let y represent total cost

a linear equation is y=mx + b
put in what we have : 64.68= 8.44x + 90
and solve for x.

Answer 2

So you just take 8.44+90 and then the answer you get from that you divide it by 64.68?

Answer 3

hold on, do you have the answer to this question? I think i made a mistake

Answer 4

I don't know how to set up the equation

Answer 5

@reynad

Answer 6

oh sorry i found my mistake. it's supposed to be 8.44x + 64.68=90 then solve

Answer 7

Ali rented a truck for one day. There was a base fee of
$17.99
, and there was an additional charge of
76
cents for each mile driven. Ali had to pay
$222.43
when he returned the truck. For how many miles did he drive the truck?