Question 39346
sorry for sounding so harsh here, but reading some of your/somebody's answers, it is difficult to grasp what you have done or what you truly understand about this topic.


1. d is the common difference between terms in an arithmetic series/progression. In English, it is "the amount to add on to a term to make the next term" and so on and so on. So, given the series 2,4,6,8,10,... i cannot see how you make d equal to 4?


What do you add to 2 to make 4?
What do you add to 4 to make 6?
What do you add to 6 to make 8?
What do you add to 8 to make 10? etc


All of these say "2". So, d=2.


Right: if you could not "see" this, how would you work out d in this situation? Just get 2 adjacent terms, like 6, 8 and subtract: 8-6 is 2. Job done!


Beyond this point, you seem to be using different sequences of numbers. You mention a=3. This has nothing to do with the 2,4,6,8,10 sequence in part a. So i do not follow. Please be very clear in what you require for each part of your questions.


Please:

1. read my Lesson on arithmetic series (others have probably written some Lessons too). 
2. try doing your questions yourself first after reading the lesson(s)
3. re-submit the questions (if you are still stuck) but make it clear what the sequence of numbers is for each part of the question. Currently it isn't clear and i guess that is why tutors are not answering this.


Hope this helps, somewhat :-)


Jon.