Ellie, an office manager, needs to find a courier to deliver a package. The first courier she is considering charges a fee of $10 plus $3 per kilogram. The second charges $7 plus $6 per kilogram. Ellie determines that, given her package's weight, the two courier services are equivalent in terms of cost. What is the weight? How much will it cost?

The weight of the package is 1 kilograms.

It will cost $ 13 by both the couriers services.

Step-by-step explanation:

Let the weight of her package is x kilograms

Now, according to the question:

The charges of first Courier = $10 + $3 (x)

and The charges of Second Courier = $7 + $6 (x)

Also, for x kilograms, both the charges are equal

⇒ $10 + $3 (x) = $7 + $6 (x)

or, 10 + 3x = 7 + 6x

or, 10 - 7 = 6x - 3x

⇒ 3x = 3, implies x = 3/3 = 1

⇒ The weight of the package is 1 kilograms.

It will cost : 10 + 3 (1) = $ 13 = 7 + 6 (1) by both the couriers services.