Question

Solving a decimal word problem using a linear equation of the for...

Lashonda received a $90 gift card for a coffee store. She used it in buying some coffee that cost $8.09 per pound. After buying the coffee, she had $49.55 left
on her card. How many pounds of coffee did she buy?

Answer 1

5 pounds of coffee

Explanation:

Let the number of pounds of coffee bought be 'x'.

Given:

Value on gift card = $90

Value of coffee per pound = $8.09

Money left after buying coffee = $49.55

Now, using unitary method,

1 pound cost = $8.09

∴ 'x' pounds cost =
`8.09x`

Now, Money left = Total money on gift card - Cost of coffee.

`49.55=90-8.09x\\\\8.09x=90-49.55\\\\8.09x=40.45\\\\x=(40.45)/(8.09)=5`

Therefore, Lashonda bought 5 pounds of coffee.