how many members were

Question

35 percent of the members were late.  If 455 were on time, how many members were there in all?

Answer 1

THIS IS EASY.  Read on.

a) what % were NOT LATE (i.e. on time).  call that x

455 = (x/100)M  where M is the total number of members.

Since you know x, you can solve this equation for M.