Respuesta :

stephanieijeh546

480 stamps must be given to Mark

Answer: 130 stamps.

Step-by-step explanation:

Let amount оf the stamps Debbie must give to Mark so that Mark have 120 more than she is x.    

Hence,

(580+x)-(720-x)=120

580+x-720+x=120

2x-140=120

2x=260

2*x=2*130

x=130.

So, 130 stamps Debbie must give to Mark so that Mark have 120 more than she.

Good luck an' have a nice day!