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 1035546: Write an explicit formula for the following arithmetic sequence -4,-1,2,5...
Write an recursive formula for the following arithmetic sequence -4,-1,2,5...
Write an explicit formula for the following geometric sequence 1/2,3/2,9/2...
Write an recursive formula for the following geometric sequence 1/2,3/2,9/2...
Click here to see answer by robertb(5830)

Question 1035526: Identify the 10th term for the sequence:12,6,3,3/2,...
Write the answer as an integer or fraction
Click here to see answer by robertb(5830)

Question 1035523: Given the sequence -1,2,-4,8... What is the common ratio? Write the number only
Click here to see answer by robertb(5830)

Question 1035562: A ball is dropped from a height of 20 feet and bounces back to 60% of the previous height. What is the total distance traveled?
Click here to see answer by ikleyn(52787)

Question 1035560: Find the fifth term of the following sequence: a1 = 2; an = n^2 + an-1

Click here to see answer by ikleyn(52787)

Question 1035559: after a person takes his pain medication, his kidneys filter 35% of the medicine over a four-hour period. if a patient received medicine at 8 am on a certain day, how much will be in his blood stream at midnight of the same day?

Click here to see answer by josgarithmetic(39617)

Question 1035561: Write
7
Σ81(-1/3)^(k-2)
k=2
in expanded form. then find the sum
the sum is (182/3)
i dont know how to do expanded
Click here to see answer by Edwin McCravy(20056)

Question 1035579: Find the missing term
5,6,9,15,?,40
Click here to see answer by Theo(13342)

Question 1035578: Find the sum of the series 1 + 2 + 4 + 5 + 7 + 8 + 10 + 11 + ... + 299, which is the sum of the integers from 0 to 300, leaving out the multiples of 3.
Click here to see answer by ikleyn(52787)

Question 1035587: A pendulum swings through an arc of 16 inches. On each successive swing, the length of the arc is 96% of the previous length. After 10 swings, what is the total length of the distance the pendulum has swung?
Click here to see answer by ikleyn(52787)

Question 1035525: Write the common ratio for the sequence:12,6,3,3/2,...
Write the number only
Click here to see answer by ikleyn(52787)

Question 1035575: Write
7
Σ81(-1/3)^(k-2)
k=2
in expanded form. then find the sum

Click here to see answer by Alan3354(69443)

Question 1035646: the sum of the seventh terms of a linear sequence is 38 and the ninth term is 37. find the sequence ?
Click here to see answer by Boreal(15235)

Question 1035646: the sum of the seventh terms of a linear sequence is 38 and the ninth term is 37. find the sequence ?
Click here to see answer by MathTherapy(10552)

Question 1035646: the sum of the seventh terms of a linear sequence is 38 and the ninth term is 37. find the sequence ?
Click here to see answer by ikleyn(52787)

Question 1035723: the 1st term of A.P is -12 and last term is 40. if the sum of the series is 196,find the number of terms and the common difference.
Click here to see answer by rothauserc(4718)

Question 1035832: Evaluate the infinite geometric series 0.79 + 0.079 + 0.0079 + 0.00079 + 0.000079. Express your answer as a fraction with integer numerator and denominator.
Click here to see answer by robertb(5830)

Question 1035833: Compute the sum
(2)/(1*2*3) + (2)/(2*3*4) + (2)/(3*4*5) + ...
Click here to see answer by robertb(5830)

Question 1035975: What is the nth term for the following sequence please: 250, 280, 310, 340 and 370.
Also other than actually working it out logically and time consumingly, what is the 10th term of the above sequence, thank you very muchl.
Click here to see answer by FrankM(1040)

Question 1035986: Find the sum of the 1st to 50th terms where a1= 2.1 and a50= 1.2
Click here to see answer by ikleyn(52787)

Question 1035986: Find the sum of the 1st to 50th terms where a1= 2.1 and a50= 1.2
Click here to see answer by robertb(5830)

Question 1035951: 0,3,8,60,51,62,93,45,?, 0,120,440,960
Click here to see answer by Alan3354(69443)

Question 1035928: an=a1-3^n
Click here to see answer by ikleyn(52787)

Question 1035956: What number should came next in the sequence 0,2,4,6,9,12,16,x
Click here to see answer by Edwin McCravy(20056)

Question 1036079: A certain arithmetic sequence has this explicit formula for the nth term:
an = 11 + (n - 1)(4)
The same sequence has this recursive formula:
an = an-1 +
What number belongs in the blank space in the recursive formula?

Click here to see answer by fractalier(6550)

Question 1036157: If the first term in an arithmetic sequence is 15 and the tenth term is 69. What is the fourth term in the sequence?
Click here to see answer by josgarithmetic(39617)

Question 1036199: The difference between the tenth term and the seventh term of an arithmetic sequence is -60. The twelfth term divided by the sixth term is 2. Find the first term and the common difference.
Click here to see answer by robertb(5830)

Question 1036257: In an A.P, the sum of three positive consecutive numbers is 21. The sum of their squares is 155.Find the numbers
Click here to see answer by ikleyn(52787)

Question 1036461: Compute the sum
1 + 1/3 + 2/3 + 2/9 + 4/9 + 4/27 + 8/27 + 8/81...

Thanks!
Click here to see answer by Theo(13342)

Question 1036462: Compute
1 - 2 + 3 - 4 + ... + 2005 - 2006
Thanks!
Click here to see answer by Aldorozos(172)

Question 1036463: Compute the sum
1 + 1/3 + 2/3 + 2/9 + 4/9 + 4/27 + 8/27 + 8/81...
Click here to see answer by stanbon(75887)

Question 1036491: Write the explicit formula for the arithmetic sequence where t underscore 7 =121 and t underscore 15 =193 .

Click here to see answer by stanbon(75887)

Question 1036497: Alpha writes the infinite arithmetic sequence
10, 8, 6, 4, 2, 0 ...
Beta writes the infinite geometric sequence
9, 6, 4, 8/3, 16/9 ...
Gamma makes a sequence whose nth term is the product of the nth term of Alpha's sequence and the nth term of Beta's sequence:
10 * 9, 8 * 6, 6 * 4, 4 * 8/3, 2 * 16/9, ...
What is the sum of Gamma's entire sequence?
Click here to see answer by robertb(5830)

Question 1036637: What are two other ways to represent this expression: (5k+1)(k^2-3)+7
Click here to see answer by JBarnum(2146)

Question 1036673: Find the sum of the infinite geometric series, if possible.
64 + 32 + 16 + . . .
(a) 128
(b) 127
(c) no sum
(d) 130
(e) 131

Click here to see answer by richard1234(7193)

Question 1036710: 0,3,8,60,51,62,93,45,?,0,120,440,960
Click here to see answer by Edwin McCravy(20056)

Question 1036714: 1,2,9,28,65... which number is next of this series?
Click here to see answer by rothauserc(4718)

Question 1036737: In an arithmetic progression, the thirteenth term
Is 27, and the seven term is three times the second term.find the first term and the common differences.
Click here to see answer by ikleyn(52787)

Question 1036936: 7
Click here to see answer by Alan3354(69443)

Question 1037125: if one dollar in Angel Island money is worth $1.41 in Hydrocity money, how much is $100 in Hydrocity money worth in Angel Island money, to the nearest cent?
Click here to see answer by ikleyn(52787)

Question 1037135:
Click here to see answer by ikleyn(52787)

Question 1037189: The following terms are the beginning of a feometric sequence, where p < 0:
24, -6p, 9pt, -9t
Find the value of p and t.
I've been stuck on this problem for the last 15 minutes and I've had no luck!
Click here to see answer by ikleyn(52787)

Question 1037098: 1 - 4/5 - 3/5 - 8/17 - 5/13 - ...????
LOGICA?
Click here to see answer by Edwin McCravy(20056)

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