Question

ABC shipping charges $7 plus $1 a pound to ship an overnight package. XYZ shipping charges $10 plus $0.75 a pound to ship an overnight package. For what weight is the charge the same for the two companies?

Answer 1

x = lbs

y = total cost

ABC shipping: $7 + $1x = y

XYZ shipping: $10 + $0.75x = y

We set each equation equal to the other.

$7 + $1x = $10 + $0.75x. Subtract $7 from both sides and subtract $0.75x from both sides

$0.25x = $3. Divide each side by $0.25.

x = 12 lbs

When a package is 12lbs the cost is the same.