SOLUTION: Find S[5] for the arithmetic sequence with a[3]=39 and a[5] =61

Question 835036: Find S[5] for the arithmetic sequence with
a[3]=39 and a[5] =61
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Find S[5] for the arithmetic sequence with
a[3]=39 and a[5] =61
----
a(3) = a + 2d = 39
a(5) = a + 4d = 61
----
Subtract to solve for "d":
2d = 22
d = 11
-------
Solve for "a":
a + 2d = 39
a = 39-2*11
a = 17
--------
To find S(5)
S(n) = (n/2)(a+L)
S(5) = (5/2)(17+61) = 5(39) = 195
=========================
Cheers,
Stan H.

RELATED QUESTIONS
For a geometric sequence with {{{r=1.5}}} and {{{S[5]=92.3125}}}. Find... (answered by jim_thompson5910)

Find 'n' for an arithmetic sequence for which Sn= 345, a=12, and d=5. (answered by ewatrrr)

Find 'n' for an arithmetic sequence for which Sn=345, a=12, and... (answered by ewatrrr)

Please I will Cashapp 10$ If anyone can solve it it's due today I really need help.... (answered by Boreal)

Please help me with this problem: The 15th term of an arithmetic sequence is 74, and the (answered by stanbon)

Find the 3rd term of an arithmetic sequence with t2 =9/2 and t5 = 6. A. 5 B. 4 (answered by MathLover1)

The first term of a sequence are 1, -5/2, 2, and -3/2. determine whether the sequence is... (answered by stanbon)

If the given terms are part of an arithmetic sequence, write a rule for the sequence,... (answered by josgarithmetic)

1. What must be the value of k so that 5k-3, k+2, and 3k-11 will form an arithmetic... (answered by ikleyn,MathTherapy)