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 995748: 3 6 17 42 87 158 find the sequence

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Question 995916: Help is urgently needed.
Find the remainder when x^100 + 2x^99 +3x^98 +... 100x is divided by
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Question 995916: Help is urgently needed.
Find the remainder when x^100 + 2x^99 +3x^98 +... 100x is divided by
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Question 995915: Please help.
The sum of the integers between 10 and 65, inclusive, which are divisible by 2 and 3 is _____
Thanks in advance!
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Question 996147: Find the sum to n terms of the series:2+10+30+65+130+...
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Question 996147: Find the sum to n terms of the series:2+10+30+65+130+...
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Question 996525: Write the equation for the general term of the sequence {-2, 4, -8, 16 . . . }.
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Question 995635: I have to use one of the arithmetic series formula. The arithmetic series 5 + 9 + 13 +...+ tn has a sum of 945. How many terms does this series have?
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Question 996734: The sum of the first 50 elements of a set is 6925 with a common difference of 5. What is the first element of the set.

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Question 996711: what is the similarity between 85 19 17 4 2
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Question 996947: What is the similarity between 85,17,19,4 and 2
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Question 996958: What is the similarity between numbers 85,19,17,4,2?
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Question 996991: Evaluate S5 for 400 + 200 + 100 + � and select the correct answer below.
25
775
1,125
500
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Question 997492: What is the similarity between 85,17,19,4,2 ?
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Question 997518: 01/01/1900, the day was Monday. If any year is input through keyboard, Find out day on 1st Jan of that year.
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Question 997811: The sum of three numbers in a.p is 12 and the sum of their squares is 66. what are the numbers
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Question 997880: In a AP the sum of the three postive consecutive number is 21 and the sum of their sqaure is 155.find the number?
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Question 998073: The sum of the first eight terms of an A.P. is 4 and the sum of the first twelve terms is 78. Find the sum of the first 30 terms.
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Question 998264: Find the sum of first 15 terms of an AP., whose nth term is 3-2n.
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Question 998294: What is the 30th term of the sequence: -34, -29, -24, -19
Click here to see answer by Edwin McCravy(20056)

Question 998312: By using the formula for the sum of n terms of a Geometric Progression, find the sum of the first 10 terms of the series 62.5, -25, 10, -4......, correct to 3 decimal place.
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Question 998359: Please help me solve this equation. The second and seventh term of a g.p are 18 and 4374 respectively find the (a) common ratio (b) sum of 4th and 8th terms (c) sum of the first 10 terms please help me
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Question 998353:
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Question 998395: What are the next three terms of 0, -15, -30, -45, -60?
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Question 998451: the fifth abd fifteenth term of an AP is 13 and 17 .find the sum of first 21 term
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Question 998451: the fifth abd fifteenth term of an AP is 13 and 17 .find the sum of first 21 term
Click here to see answer by MathTherapy(10552)

Question 998498: three numbers are in arithmetic progression. their sum and sum of their squares is 126. find the smallest number of the arithmetic progression
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Question 998497: three numbers are in arithmetic progression. their sum and sum of their squares is 126. find the smallest number of the arithmetic progression
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Question 998564: any AP series and find the sum of first 21 terms

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Question 998549: For the sequence given by an=4n+5, answer the following:
a. Find the first five terms
b. Find the sum of the first 25 terms
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Question 998587: How can I find the sum of the first n multiples of 4?
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Question 998665: Arrange the following fraction into increasing value 3/4,3/6,and 3/2
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Question 998671: 1 , 8 , 18 ...
in the sequence above , the first term is 1 and the sum of the first n terms is equal to 3 to the power n for all n > 1
what is the fourth term in the sequence ?
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Question 998667: The average of some Natural number is 15 if 30 is added to first number and 5 is subtracted from the last number the average becomes 17.5 then the no. Of natural no. Is
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Question 998766: The mean of the first five terms of an arithmetic sequence is 27, and the mean of the first eight terms of the same sequence is 39. What is the absolute difference between the first and second terms of this sequence?

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Question 998907: AnAP has 15 term and a common difference of -3 find the first and last term if its sum is 120
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Question 999052: How many three terms APs are possible whose elements belongs to a given set of natural numbers {1,2,3,4,5,.....,40} and common difference is a positive integer
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Question 997978: if logarithm a + logarithm b + logarithm c +.......,is an arithmetic progression, show that a+b+c +.........is a geometric progression

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Question 999110: Conclude the following sequence
1/2;1;1/2;...
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Question 999190: The distance between 100 and me is 57. What numbers can i be?
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Question 999274: what is the difference between 85 17 19 4 and 1?
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Question 999294: The first term of a geometric sequence is 1/1024 and the common ratio are 1/4
a) find the first term
b)Find the sum of the first 15 terms.
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Question 999276: what comes next in sequence of 5,25,10,100...........?
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Question 999211: Given the formula f(n) = 3(-1)n find the first 5 terms of this sequence
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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