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 209963: it says find Sn for each arithmetic series described. a1=20, an=112, d=4. how do i find it ?
Click here to see answer by stanbon(75887)

Question 210038: my question is sn=800 r=1.2 a=10 how to find n?
Click here to see answer by nyc_function(2741)

Question 210252: make a conjecture in terms of Q(n)(find the nth term) for the following sequence & then find the 100th term:n= 1 2 3 4 5 6
Q= 3 12 25 42 63 88
Cannot figure out any part of this...I would really appreciate any help at this point!
Thanks!
Click here to see answer by scott8148(6628)

Question 210039: ok, complete question is
a gardener has been given the task to digging an area of 800 square meters. it is expected that he will dig 10 square meters on the first day and on each successive day he will dig 1.2 times more than the area he dug on the previous day. find the number of days the gardener will take to complete the task?
Click here to see answer by ankor@dixie-net.com(22740)

Question 210845: -1, 4, -16, 64.. what is the rule for this sequence?
Click here to see answer by josmiceli(19441)

Question 211066: Can you help me answer this problems ?
1. Find a number that is 96 greater than its opposite.
2. Find a number whose product with 9 is the same as its sum with 56.

Click here to see answer by stanbon(75887)

Question 211357: please help me find the value of (u sub one).
u sub zero =16
u sub n=(1-0.005)u sub n-1+16
where n > or = to 1

Click here to see answer by Theo(13342)

Question 212061: 2,6,10,14....... find the 15th term
Click here to see answer by Edwin McCravy(20056)

Question 212061: 2,6,10,14....... find the 15th term
Click here to see answer by Earlsdon(6294)

Question 212504: sequence 4,7,10,....
formula 3n+1
if two numbers of the sequence are multiplied need to show proof that result is always a number in this sequence.
please give guidance
Click here to see answer by stanbon(75887)

Question 212918: The question is: Three consecutive terms of a geometric sequence have a sum of 28 and a product of 512. Find these numbers.
(Hint: let these numbers be a/r, a and ar )
I really don't understand the question, anyone kindly help me??
Thanks
Click here to see answer by josmiceli(19441)

Question 212953: c=210+c
Click here to see answer by rapaljer(4671)

Question 213568: Please help me find 2 consecutive even integers whose sum is 217. The best I got was 106.6 and 108.8 but still fall short. I have these a lot and need to know how to find these with a simple math trick or formula. (Algebra 1) Thanks
Click here to see answer by drj(1380)

Question 213500: Im really bad at math. HELP Find a5 and An for each geometric sequence. a2=-4,r=3
Click here to see answer by scott8148(6628)

Question 211895: what is the 20th term for this set of numbers? 12, 19,26, 33
Click here to see answer by drj(1380)

Question 213951: Am totally new to sequences and kinda lost on this problem. Need help for mathletes competition tomorrow
What is the 21st term of the sequence 3,6,12,24
Click here to see answer by stanbon(75887)

Question 214017: 8 16 14 10 whats the next 3 numbers in the sequence
Click here to see answer by HyperBrain(694)

Question 214365: find the nth term of an A.P. whose (r+1)th term is 4r-3
Click here to see answer by stanbon(75887)

Question 214501: There are three numbers in the ratio of 2:3:4. The sum of their squares is 464. Find the numbers.
Click here to see answer by rfer(16322)

Question 215270: On Exercise 2 page 48 chapter 1, I don't know how to solve each equation.
Click here to see answer by drj(1380)

Question 215440: solve r=a+(n-1) d for d
Click here to see answer by vleith(2983)

Question 215706: 4-7i divided by 5+6i
I understand that you have to foil the opposite of the denomenator, but i have trouble simplifying. I got as far as 20-59i+42i^2 over 25-36i^2.
I hope you understand my question. Thank you.
Click here to see answer by scott8148(6628)

Question 216171: describe each sequence using words and symbols
sequences and equations
46,52,58,64,....
Click here to see answer by checkley77(12844)

Question 216244: Please help me find the next number in the sequence,
1,7,31,127,...
Click here to see answer by stanbon(75887)

Question 216598: I need help finding out what the numbers are going up by.
The sequence is 2,3,5,7,11
Click here to see answer by ichudov(507)

Question 216598: I need help finding out what the numbers are going up by.
The sequence is 2,3,5,7,11
Click here to see answer by DRichardson(63)

Question 216229: what is the formula for this sequence 0, 2, 5, 9, 14
Click here to see answer by ichudov(507)

Question 217318: The third term of an arithmetic sequence is 4 and the sum of the first 8 term is 36. Write down the first 8 term of the sequence.

Click here to see answer by drj(1380)

Question 217741: How do you work this problem? A-R=R
Click here to see answer by RAY100(1637)

Question 217752: The product of twice a number and three is the same as the difference of five times the n umber an d 3/4. Find the equation and solve.
Click here to see answer by RAY100(1637)

Question 218437: 1*3+3*5+5*7+7*9+9*11+11*13+13*15+15*17
Click here to see answer by tlouvierre(4)

Question 219879: What is the next number: 62,53,44,71,17
Click here to see answer by stanbon(75887)

Question 219869: The sum of two consecutive terms in the arithmetic sequence 1, 4, 7, 10, ... is 299. Find these two terms.
Please help! :)
Click here to see answer by scott8148(6628)

Question 219958: Miriam is four years older than Ricardo. Ten years ago, Miriam was 3 times as old as Ricardo was then. How old are they now? Set up an equation and solve.
Please help! :)
Click here to see answer by ankor@dixie-net.com(22740)

Question 220545: The sum of three numbers is 105. The second number is 10 larger than the first and the third is one-half the second. Find the three numbers.

Click here to see answer by stanbon(75887)

Question 221265: 3s + 1d = �3.50
2d + 1s =�3.25
What does S and D equal

Click here to see answer by Alan3354(69443)

Question 221574: Solve the formula A = 2pierh + 2pier^2 for h.
Click here to see answer by Alan3354(69443)

Question 221632: "write and solve an equation to find the nth term of each aritmetic sequence"
3,7,11,15, . . . n=8
10,5,0,-5, . . . n=21
34,49,64,79, . . . n=200

Click here to see answer by stanbon(75887)

Question 222061: number sequences
start with 3 and multiply by 3 each time, How do you find the 20th term there must be an easy way without having to count all the way up.
Click here to see answer by solver91311(24713)

Question 222447: what is the missing term: 1,4,16,-,256?
Click here to see answer by vleith(2983)

Question 222445: A ball is dropped from 13.5ft, after each bounce the ball goes up by 60% of the previous bounce. How high will the ball go after the 38th bounce?
Click here to see answer by solver91311(24713)

Question 222358: hey there thanks ,the question is-
the difference between two numbers is 4 and the sum of their squares is80 less than three times their product. Find the numbers
thanks again.
xx

Click here to see answer by ankor@dixie-net.com(22740)

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