in a certain apartment building, the ratio of tentants to cars is 3:5. If there are 30 tentants, how many cars are there? 10 poi
2 answers:
You might be interested in
Looks like you just evaluated the summand for the given value of 
, whereas the question is asking you to find the value of the sum for the first terms.
Let
. Then 
is the 
th partial sum.
happens to be the first term in the series, which is why that box is marked correct:
But the next partial sum is not correct:
and this is not the same notion as the second term (which indeed is 0.75) in the series.
Let
But the next partial sum is not correct:
and this is not the same notion as the second term (which indeed is 0.75) in the series.