Two numbers are in the ratio 5:3.if they deffer by 18,what are the numbers?

Which equation represents the partial sum of the geometric series?

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

Nick has box brads. he uses 4 brads for the first project. nick let’s b represent the original number of brads and finds that for the second project, the number of brads he uses is 8 more than half the difference of b and 4. write an expression to represent the number of brads he uses for the second project.