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 1023457: Solve this sequence
54, 348, X, 16812, 117654, 823548
I cannot figure out what X is at all -_-
Click here to see answer by robertb(5830)

Question 1022913: Please help me to find next number....
5,17,22,26,_,_
Click here to see answer by Edwin McCravy(20056)

Question 1023560: In a geometric progression,the 6th term is 96 and the common ratio is -2. Find the sum of the first 6 terms of the progression.
Click here to see answer by ikleyn(52788)

Question 1023563: A sequence has 12 elements. The six elements form a geometric progression and the last seven elements form an arithmetic progression. If the first element is 3 and the sixth element is -96,find the sum of the first six terms and the 10th element if the 12th element is -72.
Click here to see answer by ikleyn(52788)

Question 1023561: A stack of wood has 44 pieces on the bottom row and 40 in top of those,then 36, and so on. If there are 260 pieces of firewood, how many rows are there in the stack?
Click here to see answer by josgarithmetic(39618)

Question 1023578: Find the smallest positive term of the progression 100, 97, 94...(Don't enumerate)
Click here to see answer by Theo(13342)

Question 1023562: The digits of a three digit number form an arithmetic
progression. If the first and second digits are
decreased by 1 and the the third is increased by 3,
the digits will form a geometric progression.
What is the original number,if the sum of the digits
is 12?
Click here to see answer by Edwin McCravy(20056)

Question 1023725: Find the sum of the first sixteen.

Click here to see answer by robertb(5830)

Question 1023725: Find the sum of the first sixteen.

Click here to see answer by Alan3354(69443)

Question 1023742: 7,11,10,10,17,37,76 what is the eighth term
Click here to see answer by Edwin McCravy(20056)

Question 1023888: Given the sequence 4;X-2;32...
1.1 Which term of the sequence is 158?

Click here to see answer by MathLover1(20850)

Question 1023912: 17, 2, 21, 40, � is an arithmetic sequence.

True
False

Click here to see answer by fractalier(6550)

Question 1024036: Please answer this: 963, 899, 843, 795, ?

Click here to see answer by ikleyn(52788)

Question 1024036: Please answer this: 963, 899, 843, 795, ?

Click here to see answer by TigerAlgebra(40)

Question 1024030: Use Binomial Theorem To Show That {{27}}^1/5 = 1.933
Click here to see answer by robertb(5830)

Question 1024021: Please Help Me With This: Show That Sqrt{{(9+x^2)}}= 3 + x^2/6 - x^4/216. For What Value Of x is the expansion valid?
Click here to see answer by ankor@dixie-net.com(22740)

Question 1024021: Please Help Me With This: Show That Sqrt{{(9+x^2)}}= 3 + x^2/6 - x^4/216. For What Value Of x is the expansion valid?
Click here to see answer by robertb(5830)

Question 1024019: Please Help Me With This: Show That (27)^1/5=1.933
Click here to see answer by Cromlix(4381)

Question 1024112: Write the series -4 + (-1) + 2 + 5 + 8 + 11 using SUMMATION NOTATION.
Click here to see answer by fractalier(6550)

Question 1024129: 1to 29 only odd numbers,in these by which three numbers additional gives the answer 30
Click here to see answer by Alan3354(69443)

Question 1024256: Find the sum of the series 2+3/2+1+5/8+....

Click here to see answer by ikleyn(52788)

Question 1024267: what is the similarity between 85,19,17,4 and2?
Click here to see answer by ikleyn(52788)

Question 1024168: A GP has the second term as 9 and the fourth term as 81,find the sum of the list as the fourth term
Click here to see answer by Fombitz(32388)

Question 1024309: what is the distance between the points (4 5) and (1 1)

Click here to see answer by fractalier(6550)

Question 1024322: 4-3+4 1/8-1 3/4
Click here to see answer by Fombitz(32388)

Question 1024327: 1. What is the next three terms of each sequence
82,75,68,61,54
5,6,8,11,15,20
2,4,8,16,32,64
2.Give two other names for AB other than BA

Click here to see answer by ikleyn(52788)

Question 1024492: In the table below, what is the missing number? Table: Number Number: Number: Part 1: 124 300 480 Part 2: 186 450 720 Part 3: 279 675 1080 Part 4: 417 1012.5 ????
Click here to see answer by fractalier(6550)

Question 1024482: In the table below, what is the missing number? Table: Number Number: Number: Part 1: 124 300 480 Part 2: 186 450 720 Part 3: 279 675 1080 Part 4: 417 1012.5 ????
Click here to see answer by fractalier(6550)

Question 1024606: What comes next in this sequence?
3, -6, 12, 4, 20, ?
Click here to see answer by FrankM(1040)

Question 1024765: Please help me. Show all steps. Thanks
Given the geometric sequence: 33,121,4811...
Sequences
Find an explicit formula for an.
a_n=

Find a_10=

2. The purchase value of an office computer is 12690 dollars. Its annual depreciation is 1896 dollars.
The value of the computer after 6 years is dollars.
Click here to see answer by stanbon(75887)

Question 1024769: Help me please. Thanks

A pianist plans to play 6 pieces at a recital. In how many ways can she arrange these pieces in the program?
Your answer is
Click here to see answer by Alan3354(69443)

Question 1024768: Please help and show all steps. Thanks
A man gets a job with a salary of 39200 dollars a year. He is promised a 2800 dollars raise each subsequent year.
His total earning for a 5-year period is dollars.
Click here to see answer by stanbon(75887)

Question 1024767: I'm very confused on this problem. Will someone please help me and show all work. Thanks
1. Suppose you go to a company that pays 0.02 for the first day, 0.04 for the second day, 0.08 for the third day and so on. If the daily wage keeps doubling, what will your total income be for working 31 days ?
Total Income =

2. Determine the seating capacity of an auditorium with 40 rows of seats if there are 15 seats in the first row, 17 seats in the second row, 19 seats in the third row, 21 seats in the forth row, and so on.
Total number of seats =
Click here to see answer by ikleyn(52788)

Question 1024766: Please help and show work. Thanks
Sequences

For the sequence a_n=2−2⋅(n−1),
its first term is ;
its second term is ;
its third term is ;
its fourth term is ;
its fifth term is ;
its common difference d=

Click here to see answer by josgarithmetic(39618)

Question 1024792: Create and simplify an algebraic expression for the following sequence of operations to prove the result is 1 used N to represent thee number chosen. Think of a number. Add 3. Double that. Subtract 4. Cut that in half. Subtract your original number. Your result is 1!
Click here to see answer by ikleyn(52788)

Question 1024763: Sum of (1, 5 k(k+1)/2, 25 k(k+1)(k+2)/6, 125k(k+1)(k+2) (k+3)/24, �� )
Click here to see answer by robertb(5830)

Question 1024880: Hello, I would to ask the general formula of the sequence:
1
1
-1
-1
1
1
-1
-1
1
1
the pattern goes on and on. Thank you!
Click here to see answer by Edwin McCravy(20056)

Question 1024899: Please help me I have tried this problem over and over again and this is the answer I came up with.(-2In(c))(In(a)-3In(b))^-3
-3(5)+(2+3)^-3
-15+(6)^-3
-15+-216=-231
Ans.-231

Problem (d) (ln c^−2)(ln a/b^−3)^−3=

Click here to see answer by Alan3354(69443)

Question 1024896: I'm very confused on this problem haven't did problems like this over 10 years. please help me and show all work. Thanks
1. Suppose you go to a company that pays 0.02 for the first day, 0.04 for the second day, 0.08 for the third day and so on. If the daily wage keeps doubling, what will your total income be for working 31 days ?
Total Income =

2. Determine the seating capacity of an auditorium with 40 rows of seats if there are 15 seats in the first row, 17 seats in the second row, 19 seats in the third row, 21 seats in the forth row, and so on.
Total number of seats = ''.

Click here to see answer by Alan3354(69443)

Question 1025112: Please help me this problem is driving me crazy.
Write the sum using sigma notation:
1/1⋅2+1/2⋅3+1/3⋅4+⋯+1/219⋅220=
A
∑ B
n=1
, where
A=

B=

Click here to see answer by richard1234(7193)

Question 1025235: 20(8)36 , 20(12)53 ,18(11) ...? what is next?
Click here to see answer by ikleyn(52788)

Question 1025297: What is 5 times r
Click here to see answer by Fombitz(32388)

Question 1025299: if Tn=n^2,find 19th term if n is even.
Click here to see answer by Fombitz(32388)

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, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790