Find the three geometric means between 15 and 1215

Question

anonymous · Answer

@nikato

nikato · Answer

sorry about that.
do u still need help? @StaceyMarie

nikato · Answer

well whether u finish ur problem or not. u have 15,_,_,_,1215 15 is the 1st term and 1215 is the 5th

plug it into the geometric sequence formula
n=ar^n-1
where n=term
a=first term of sequence
r=ratio
n=# of terms

to solve the problem the first thing to do is to find r

nikato · Answer

so plug in 15 and 1215 and divide the 2 to find r

1215=15r^4
-------------
15     =15r^0

so
81=r^4
r=3

so to find the term term just multiply the previous term by 3. do this 3 times to fidn the three geometric means

anonymous · Answer

Oh thank you but I figured it out. it was actually pretty simple when I understood it a bit better

nikato · Answer

no problem. and yea, thsi problem wasnt that difficult, just lengthy