SOLUTION: sum of first 20 terms of an arithmetic sequence is 900. sixth term is 27. what is its fifteenth term and common difference.

Question 755524: sum of first 20 terms of an arithmetic sequence is 900. sixth term is 27. what is
its fifteenth term and common difference.

Answer by reviewermath(1029) (Show Source): You can put this solution on YOUR website!
Q:
sum of first 20 terms of an arithmetic sequence is 900. sixth term is 27. what is
its fifteenth term and common difference.
-------------------------------------------------------------------
A:
In arithmetic sequence, the sum of the first n terms is equal to
=
The sixth term is = 27, if the common difference is d then the first term is = 27 - 5d and the 20th term is = 27 + 14d.
=
900 =
900 =
9d + 54 = 90
d = 4
= 27 - 5(4) = 7
The nth term is = 7 + 4(n - 1) = 4n + 3
The 15th term is = 4(15) + 3 = 63
Here are the answers:
15th term: and common difference, d =
RELATED QUESTIONS
the sum of the first twelve terms of an arithmetic sequence is 1188. if the sixth term is (answered by josgarithmetic)

The first term of an arithmetic sequence is -3 and the fifteenth term is 53. What is the... (answered by MathLover1,MathTherapy,greenestamps,ikleyn)

4th term Of an arithmetic sequence is 17. Sum of first 20 terms is 990. Find first term... (answered by mananth)

What is the fifteenth terms of the arithmetic progression whose first term is 6 and... (answered by MathLover1,ikleyn)

the sum of the first fifteen terms of an arithmetic terms progression is 270. find the... (answered by ewatrrr)

The difference between the tenth term and the seventh term of an arithmetic sequence is... (answered by robertb)

In an arithmetic sequence of positive numbers, the common difference is twice the first... (answered by palanisamy)

the sum of the first and last terms of an arithmetic progression is 42.the sum of all the (answered by ikleyn)

4. In an arithmetic sequence, the first term is 3 and the second term is 7. a. Find the (answered by Boreal)