Finding the nth term
Find the nth term in these sequences:
a) 4, 10, 18, 28, 40
b) 0, 1, 4, 9, 16
c) 5, 12, 23, 38, 57
A box of biscuits
A box of biscuits contains 36 biscuits. 20 biscuits have foil wrappers. 15 are chocolate biscuits with foil wrappers. If 9 are not chocolate and do not have a foil wrapper, then how many chocolate biscuits are there?
a) the sequence is:
ReplyDelete4, 10, 18, 28, 40
6 8 10 12 <=and the differences for the sequence is that
2 2 2 in the end the difference is 2 so you half that and put an n squared on the end which would give you n squared then you take that and use n = 1 as an example to get the answer. that would give you 1 squared + 3 = 4 (the first term). If you check that for n = 2 that will not work because sometimes you need to make it 1 squared + 3n for it to work. You can then use the same approach for the rest. Here are the answers if you need them.
a) n squared + 3n
b)n squared
c)2n squared + n + 2