Questions on Algebra: Sequences of numbers, series and how to sum them answered by real tutors!

Tutors Answer Your Questions about Sequences-and-series (FREE)

Question 442767: determine the common difference, the nth term and the 100th term for the arithmetic sequence
12,9,6,3
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Question 442504: determine the common difference, the nth term and the 100th term for the arithmetic sequence 12,9,6,3
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Question 441542: Write a rule for the nth term of the arithmetic sequence.
5/2, 11/6, 7/6, 1/2, -1/6
Please help!
Click here to see answer by ewatrrr(10682)

Question 442499: The second term of a geometric sequence is 10 and the fifth term is 7290. find the nth term
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Question 443307: ∞
Find the sum of the infinite geometric series ∑ 1800(1/3)^n
n=0
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Question 443320: Find a formula for S= (1/log2(N))+(1/log3(N))+(1/log4(N))+...+(1/log25(N)), where N>1.
***log2, log3, log4... are supposed to be log subscript 2 and so on but I could not type it in as a subscript***
Click here to see answer by swincher4391(726)

Question 443347: find the fourth term in the expansion of (A + 2B)^10 using the binomial theorem
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Question 443621: How would this equation be translated
One number is 5 larger than another number. Their sum is equal to 5 times their difference.
Click here to see answer by swincher4391(726)

Question 443823: Write each series in summation notation
-2 +4 -8 +16 -32
Click here to see answer by tinbar(128)

Question 444308: what is the nth term of: 3, 12, 27, 48, 75, 108...
What is the nth term of: 3, 6, 11, 18, 27,38...
What is the nth term of:4, 6.5, 9, 11.5, 14...
what is the nth term of: 20, 17, 14, 11, 8...
Please awnser fast. thanks
Click here to see answer by MathLover1(6623)

Question 444503: Hello,
I am stuck on one of the problems I have to resolve. Please help me understand step by step what needs to be done.
Problem:
"One number is 10 times as large as another, and their difference is 81. Find the numbers."
I have always had a hard time understanding these types of problems. Please help me understand so I can solve them in the future problems as well.

Thank you!!!!
Maria P.
Click here to see answer by rwm(914)

Question 444320: what is the common difference of 8, 20, 32, 44, 56
Click here to see answer by richard1234(5390)

Question 445067: find the 43rd term of each sequence
19.5, 19.9, 20.3, 20.7,
also
21, 15, 9, 3
thank you for ur help
Click here to see answer by checkley79(3050)

Question 445250: find the first sixth and twelfth terms of the sequence
A(n)=-5+(n-1)(3)
Click here to see answer by stanbon(57250)

Question 445482: Write down an algebraic formula for the nth term of the sequence 2;4;8;16
Click here to see answer by jorel1380(2518)

Question 445978: simplify : 2i+7/8-3i

Click here to see answer by Gogonati(809)

Question 446254: true or false. the sequence a(n)=2,4,8,16,32,...is the same as the sequence a(1)=2, a(n)=2a(n-1).
Click here to see answer by Edwin McCravy(8882)

Question 446313: factor 2xsquared plus x minus 10
Click here to see answer by chriswen(106)

Question 446591: identify the following series as arithmetic , geometric , or neither.
1. 3a + 3a^2 + 3a^3 + 3a^4 +...+ 3a^n +...
2. -3+3-3+3-3+3....
3. n=1 (3+na) >> above this is a sideways 8 and a sideways M <<<
Click here to see answer by richard1234(5390)

Question 447147: For any integers n, let ® n be defined as the sum of the distinct prime factors of n. For instance, ® 36=5, because 2 and 3 are the only prime factors of 36 and
2+3=5.
What is the smallest value of w for which ® w=12 ?

Click here to see answer by richard1234(5390)

Question 447497: what is the sum of the series 6+9+12 ... +30
Click here to see answer by ewatrrr(10682)

Question 447184: for the sequence, describe the pattern, write the next term, and write a rule for the nth term.
-3, 6, -9, 12...
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Question 447631: Hugh Moore makes up a joke and tells it to his 5 closest friends on Sunday morning. Each of those friends tells his or her 5 closest friends on Monday morning, and so on. Assuming no duplication, how many people will have heard the joke by the end of Saturday?
If you could help me with this problem, I would appreciate it.
Click here to see answer by josmiceli(9661)

Question 447635: A pile driver drives a post 9 feet into the ground on its first hit. Each additional hit drives the post 2/3 the distance of the prior hit.
a) find the total distance the post has been driven after 4 hits.
b) what is the greatest distance the pole could be driven into the ground?
If you could help me with this problem, I would really appreciate it. Thanks.
Click here to see answer by solver91311(16870)

Question 447707: There are two numbers whose sum is 9 and the difference is five . What are the two numbers?
Click here to see answer by stanbon(57250)

Question 447707: There are two numbers whose sum is 9 and the difference is five . What are the two numbers?
Click here to see answer by solver91311(16870)

Question 447707: There are two numbers whose sum is 9 and the difference is five . What are the two numbers?
Click here to see answer by Leaf W.(97)

Question 448007: Find the 29th term in the follwing seqeunce 21,15,9,3
Click here to see answer by ewatrrr(10682)

Question 448008: Is the following sequence arithemtic? if,so idenitfy the common difference of -16,-22,-29,-37
Click here to see answer by Edwin McCravy(8882)

Question 448029: how many ways can ten applicants line up for a job interview
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Question 448035: A pizza restraunt offers nine choices of vegetarian toppings for pizza. In how many ways can you choose 4 toppings?
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Question 448025: Insert arithmetic means between 7 and 71 in such a way that the 5th arithmetic mean is 27. Find the number of arithmetic means.
Click here to see answer by Edwin McCravy(8882)

Question 448455: The given series has 6 terms. What is the sum of the terms in the series 5+8+11 . . +20
Click here to see answer by ewatrrr(10682)

Question 448470: How to define the given series for 7 terms -13+-16+-19+....
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Question 448459: Evaluate the series 2+8+32+128+512+2048
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Question 448472: Evaluate the series 4+8+16 to S[6]
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Question 448471: Does the following infinite geometric series diverage or converge? explain. 7+21+63+189...
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Question 448458: Does the following infinite geometric series diverge or converge? Explain. 7+21+63+189
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Question 448474: Find the 8th term in the following geometric Sequence 28,14,7,3.5
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Question 448452: A disc jockey wants to select 4 songs from his new c.d that contains 12 songs. How many ways can the dick jockey choose 4 songs?
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Question 448476: Use the geometric mean to find the 7th term in a geometric sequence if the 6th term is 8 and the 8th term is 8
Click here to see answer by Edwin McCravy(8882)

Question 448454: The sequence is recursive. Find the value of the next term in the sequence. 5,8,11,14,17
Click here to see answer by ewatrrr(10682)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645