math
posted by
Lola on
.
Find the rule for 9,16.8, 24.6, 32.4

math 
Ms. Sue,
16.8  9 = 7.8

math 
Lola,
i left out the part that you need to put it in nth term

math 
Anonymous,
a(n)=a(n1)+7.8
OR
a(n)=a1+(n1)*d
a(n)=9+(n1)*7.8
In google type:
arithmetic progression
When you see list of results click on some site.
wikipedia is good choice