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 1069940: Find S5 for the series -2 + -10 + -50 + -250 +...
Click here to see answer by ikleyn(52788)

Question 1070019: Determine the values of x for which the series converges
1+(1/2x-1)+1/(2x-1)^2+.....
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Question 1070091: what is the next number in the sequence 7,2,0,7,8,4,3.
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Question 1069954: 1 3 5 are the first three terms of the first differences of a quadratic sequence. The 7th term of the quadratic sequence is 35.
1.determine the 6th and 5th terms of the quadratic sequence (4)
2.Determine the nth term of the quadratic sequence(5)
Click here to see answer by KMST(5328)

Question 1070260: An arithmetic and geometric series both have the same first terms,a=9. The fifth term of the arithmetic series is equal to the second term of the geometric series minus 1. The sum of first three terms of the geometric series is equal to the twenty eighth term of the arithmetic series. Find the ratio and common difference for each of the series(if the common difference is a whole number)
Click here to see answer by ikleyn(52788)

Question 1070326: 2,10,25,?,81,132
What is the value of question mark.
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Question 1070411: The first three terms of a sequence are given.
210, 206,202,
Find the 37
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Question 1070379: What is First Number among Following List ? 82, 113, 17
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Question 1070387: What is the next number in sequence 7, 2 , 0, 7, 8 , 4 , 3 ?
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Question 1070573:
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Question 1070573:
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Question 1070573:
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Question 1070563: 2x-4;x+5 and 3x-1 are the first three terms of an arithmetic sequence.(I) show that x=5 and write the first three terms of the sequence
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Question 1070586: Three numbers form an arithmetic sequence. The first term minus the third term is 8. When the 1st, 2nd, and 3rd terms are increased by 3, 5, and 8 respectively, the resulting numbers forms a geometric sequence. Find the common difference of the arithmetic sequence, find the first four terms of the geometric sequence, and the common ratio of the geometric sequence.
Click here to see answer by htmentor(1343)

Question 1070605: the third term of an arithmetic sequence is 34 and the 15th term is -14. Determine the first 2 terms
Click here to see answer by stanbon(75887)

Question 1070612: the sum of n terms of an arithmetic series is:Sn=5n^2-11. Determine common difference
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Question 1070709: 2,6,11,17, ...a7 find a7
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Question 1070708: 2,611,17, ...a7 find a7
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Question 1070706: Some three-digit integers have the following property: if you remove the first digit of the
number, you get a perfect square; if instead you remove the last digit of the number, you also
get a perfect square. What is the sum of all the three-digit integers with this curious property?
(A) 1013 (B) 1177 (C) 1465 (D) 1993 (E) 2016

Click here to see answer by Alan3354(69443)

Question 1070726: The 9th term and 6th term of geometric are 80 and 10.(a)find the 1st term and constant ratio.(b)find the number of terms if the last term is 5120.
Click here to see answer by Edwin McCravy(20056)

Question 1070901: The 3rd term of an arithmetic sequence is 34 and the 15th term is -14.
Determine the first 2 terms of the squence
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Question 1071138: Sn=n/2(3n+13) find t30=?
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Question 1071095: S30=5235 and A1=15
Find A30 and d
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Question 1071202: Aaron has 7 coins in his pocket there are pennies nickels dimes and quarters not all the coins are the same what is the smallest amount he could have?
Click here to see answer by josgarithmetic(39618)

Question 1071204: For the following geometric sequence, find the recursive formula.
{-80, 20, -5, ...}
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Question 1071203: Find the sixth term to the following geometric sequence:
4,-3,9/4,...
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Question 1071201: Write the explicit formula of this sequence:
3,4,5,6,7,...
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Question 1071260: The binomial (1+kx)^n where n>3. The coefficient of x^2 and x^3 are equal. Find k in terms of n
Click here to see answer by Edwin McCravy(20056)

Question 1071364: The first,third and sixth terms of an AP correspond to the first three consecutive terms of an increasing G.P.The first term of each progression is 16,the common difference is d and the common ratio of the G.P is r.
(I)Write two equations involving d and r
(ii)find the value of d and r
Find the sum of the first 20 terms
(I)the arithmetic progression
(ii)the geometric progression
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Question 1071575: A number of circles touch each other. The area of the smallest(1st) circle is 4piecm^2 and each consecutive circle has an area 9/4 times that of the previous one. If the distance of AB(line circles are on)=665/8. Line AB passes at the centre of the circles. How many are there?
Click here to see answer by Alan3354(69443)

Question 1071573: How many terms in the series 19+16+13 must be added to give a sum of 44?
Click here to see answer by Edwin McCravy(20056)

Question 1071595: 1) Find a formula for sn, n≥1, if sn is given by
3/4,4/7,5/10,6/13,7/16,...

Click here to see answer by Edwin McCravy(20056)

Question 1071655: (1.)Find the number of terms in an A. P whose sum is 1340 with the first term being 3 and the nth term 131.
(2.) The 8th term of an A. P is 9 greater than the 5th term, and the 10th is 10 times the 2nd term. Find the 6th term.
(3.) How many terms of the sequence 3+5+7+........are needed for the sum to equal 288?
Click here to see answer by KMST(5328)

Question 1071688: 1,3,5 are the first difference of a quadratic sequence the 7th is equal to 35 therefore how do I calculate 5th term and the 6th term please help me
Click here to see answer by Boreal(15235)

Question 1071717: What is the pattern? 1, -4, 9, -16
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Question 1071852: let a be the first term and d be the common difference
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Question 1071988: A geometric series that has 7 terms it starts with 1000 and decreases successively by 20 %

Click here to see answer by Edwin McCravy(20056)

Question 1072101: 6 1/3, 19, 57
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Question 1072101: 6 1/3, 19, 57
Click here to see answer by josgarithmetic(39618)

Question 1072112: What is the sequence in -9,101,-999,10001,-99999?
Click here to see answer by Edwin McCravy(20056)

Question 1072116: Write the next step in the sequence. 66a,55B,44c,33D
Click here to see answer by josgarithmetic(39618)

Question 1072119: 1=3, 3=5, 5=4, 6=3, 7=6,11=?
Click here to see answer by Alan3354(69443)

Question 1072308: 5,13,37,77,229,next no. In the series
Click here to see answer by Edwin McCravy(20056)

Question 1072334: (3!)! + (3!)� how to evaluate this without using a calculator?

Click here to see answer by Fombitz(32388)

Question 1072337: expand
(X^3-1/X^2)^6
Click here to see answer by Boreal(15235)

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