SOLUTION: Find the sum of the first 10 terms of the series defined by the formula: an = -2n + 5 a. 3 b. 2 c.-60 d. -15 A 5 inch spike is being pounded in to

Question 82644: Find the sum of the first 10 terms of the series defined by the formula:
an = -2n + 5
a. 3
b. 2
c.-60
d. -15

A 5 inch spike is being pounded in to a log. Every time you hit the hammer 1/4 of the remaining spike goes into the log. What kind of sequence or series is definied by the total distance the spike goes into the log?
a. arithmetic sequence
b. arithmetic series
c. geometric sequence
d.geometric series

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Find the sum of the first 10 terms of the series defined by the formula:
a(n) = -2n + 5
-7,-9,-11,.....,-25
S(10) = 10/2(-7+-25)
S(10) = 5(-32)
s(10) = -160
a. 3
b. 2
c.-60
d. -15
Comment: Check your problem again.
==========================================
A 5 inch spike is being pounded in to a log. Every time you hit the hammer 1/4 of the remaining spike goes into the log. What kind of sequence or series is definied by the total distance the spike goes into the log?
5, 5(1/4), 5(1/5)^2, 5(1/4)^3,....
Total distance in = 5^(1/4)^n where n=# of hammer strikes.
Geometric with a(1)=5 and r=(1/4)
===============
a. arithmetic sequence
b. arithmetic series
c. geometric sequence
d.geometric series
===================
Cheers,
Stan H.
RELATED QUESTIONS
Find the sum of the first 10 terms of the series defined by the formula: a(n) = -2n +... (answered by jim_thompson5910)

Please help me solve the following problems. I've tried to solve the problem but I don't (answered by venugopalramana)

Use the arithmetic sequence of numbers 1, 3, 5, 7, 9,�to find the following: a)What is... (answered by sarah_adam)

Use the arithmetic sequence of numbers 1. 3, 5, 7, 9,...to find the following: a) what... (answered by stanbon)

What is the sum of the first 10 terms of the sequence defined by An=4n-3? a. 37 b.... (answered by richwmiller)

I've got this problem (see below). I've worked through problems 1b - 1d, but I am stuck... (answered by stanbon)

Find the sum of the first 10 terms of geometric series starting at 10 and decreasing by a (answered by rothauserc)

The sum of the first n terms of a series is 5n^2-2n. The rth term is A)6r+3 B)10r-7... (answered by ikleyn)

The sum of the first n terms of a series is 5n^2-2n. The r-th term is... a) 6r+3 (answered by ikleyn,incline dybala)