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 1081596: Is the squence geometric? If so identify the common ratio 2, -4, -16, -36, ...
Click here to see answer by math_tutor2020(3817)

Question 1204784:
Click here to see answer by josgarithmetic(39618)

Question 1204834: Find the sum of
n
terms of the series
6
+
66
+
666
+
.
.
.
.
Click here to see answer by mananth(16946)

Question 1205019: Find the common ratio, given that it is negative, of a GP whose first term is 8 and whose 5th term is ½.
Click here to see answer by ikleyn(52788)

Question 1205017: If £100 is invested at compound interest of 8% per annum determine, the value after 10 years.
Click here to see answer by ikleyn(52788)

Question 1205020: Find the sum, to the number of terms given, of the following GPs:
a) 3 + 6 + ..., 6 terms b) 3=6+ .., 8 terms
c) 1+ ‡ + ‡+ .., 20 terms.
d) first term 5, common ratio ‡ , 5 terms
e) first term ‡ , common ratio - 1, 10 terms.
Click here to see answer by ikleyn(52788)

Question 1205021: 20. Write down the fifth term and the nth term of the following GPs:
a) 2, 4, 8, b) 2, 1, ½, c) 3, -6, 12,
d) first term 8, common ratio - ‡
e) first term 3, last term st , 6 terms
Click here to see answer by ikleyn(52788)

Question 1205016: The sum of the first three terms of a geometric sequence is 8 and the sum of the first six terms is 12.
Find the common ratio.
Click here to see answer by mananth(16946)

Question 1205016: The sum of the first three terms of a geometric sequence is 8 and the sum of the first six terms is 12.
Find the common ratio.
Click here to see answer by ikleyn(52788)

Question 1205016: The sum of the first three terms of a geometric sequence is 8 and the sum of the first six terms is 12.
Find the common ratio.
Click here to see answer by Edwin McCravy(20056)

Question 1205016: The sum of the first three terms of a geometric sequence is 8 and the sum of the first six terms is 12.
Find the common ratio.
Click here to see answer by greenestamps(13200)

Question 1205015: The 5th term of a GP is 8, the third term is 4, and the sum of the first ten terms is positive. Find the first term, the common ratio, and the sum of the first Ten years
Click here to see answer by MathLover1(20850)

Question 1205014: On commencing employment a man is paid a salary of GH&7,200 per annum and receives annual increments of
GH&350. Determine his salary in the 9th year and calculate the total salary he will receive in the first 12 years
Click here to see answer by greenestamps(13200)

Question 1205367: What is the sigma notation of these series 6-12+24-48+96-192
Click here to see answer by math_tutor2020(3817)

Question 1205379: Cheyenne tells a joke to 5 people and those 5 people tell the joke to 5 more people, and so on. Which expression shows the number of people that will hear the joke after the sixth round?

Click here to see answer by MathLover1(20850)

Question 1205433: You and your parents are working on a scrap book representing your family tree. You would like to include one page for each ancestor, and your parents want you to include a page or yourself.
How many generations can you include with keeping it fewer than 300 pages, how many pages would you need to 12 generations of ancestors, and assuming that one generation spans about 30 years, what s the earliest year that will appear in the book?
Click here to see answer by ikleyn(52788)

Question 1205594: What is the 15 terms of the arithmetic progression whose first term is 6and common difference is 7

Click here to see answer by MathLover1(20850)

Question 1205594: What is the 15 terms of the arithmetic progression whose first term is 6and common difference is 7

Click here to see answer by ikleyn(52788)

Question 1205595: What is the fifteenth terms of the arithmetic progression whose first term is 6 and common differences is 7
Click here to see answer by MathLover1(20850)

Question 1205595: What is the fifteenth terms of the arithmetic progression whose first term is 6 and common differences is 7
Click here to see answer by ikleyn(52788)

Question 1205650: Find the sum of an infinite geometric series where a1 = 180, and the common ratio is r = 3∕4 ?

Click here to see answer by math_tutor2020(3817)

Question 1205650: Find the sum of an infinite geometric series where a1 = 180, and the common ratio is r = 3∕4 ?

Click here to see answer by ikleyn(52788)

Question 1205669: The 11th term of an arithmetic sequence is 57 and the sum of
The first and fourth is 29 .
1, Determine the first three terms of the sequence.
2, Determine a formula of the nth term.
3,Is 100 a ter
m in the sequence justify your answer
Click here to see answer by josgarithmetic(39618)

Question 1205679: the nth term of a sequence is denoted by 3n(2n-1) find the sum of the first 5 terms
Click here to see answer by MathLover1(20850)

Question 1205679: the nth term of a sequence is denoted by 3n(2n-1) find the sum of the first 5 terms
Click here to see answer by ikleyn(52788)

Question 1205679: the nth term of a sequence is denoted by 3n(2n-1) find the sum of the first 5 terms
Click here to see answer by greenestamps(13200)

Question 1205956: The third term of a g.p is 12 and the first term is 48.find the sum of the first 11 terms
Click here to see answer by mananth(16946)

Question 1205956: The third term of a g.p is 12 and the first term is 48.find the sum of the first 11 terms
Click here to see answer by ikleyn(52788)

Question 1206130: a theater has 20 rows of chairs the first row has 10 chairs and each row after that has 2 more seats than the row before it
How many total seats are in the theater
Click here to see answer by ikleyn(52788)

Question 1206299: Determine if the sequence below is arithmetic or geometric and determine the common difference / ratio in simplest form.
5,8,11,...
Click here to see answer by mananth(16946)

Question 1206361: The first term is -140. Each term is equal to the previous term multiplied by a common ratio. The common ratio is 0.5. what would the term value be for the 20th term?
Click here to see answer by math_tutor2020(3817)

Question 1206481: What are the next 2 numbers?
-2 4 -6 8 -10 12
Click here to see answer by math_tutor2020(3817)

Question 1206481: What are the next 2 numbers?
-2 4 -6 8 -10 12
Click here to see answer by ikleyn(52788)

Question 1206538: Geometric Sequence in which T5 = 8T2
T4 + T6 = 240
Find the Sequence.
Click here to see answer by greenestamps(13200)

Question 1206538: Geometric Sequence in which T5 = 8T2
T4 + T6 = 240
Find the Sequence.
Click here to see answer by math_tutor2020(3817)

Question 1116320: Calculate

9^563 mod907

Identify which one of the following options gives the correct solution for the above expression ?

310

520

630

493

My working:

9^563 mod 907
First I identified the exponents.
9^1 mod 907
9^2 mod 907
9^16 mod 907
9^32 mod 907
9^512 mod 907
(512+32+16+2+1=563)
9^1 mod 907=9
9^2 mod 907=81
9^16 mod 907 =669
9^32 mod 907 =410
9^512 mod 907=862
To show my working between 9^32 mod 907 and 9^512 mod 907
9^64 mod 907= 410^2 mod 907 =305
9^128 mod 907=305^2 mod 907=511
9^256 mod 907 =511^2 mod 907 = 812
9^512 mod 907= 812^2 mod 907=862
But I am not sure what is the final step....

Click here to see answer by math_tutor2020(3817)

Question 1206704: A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is bell-shaped and has a mean of 48 months and a standard deviation of 6 months. Using the 68-95-99.7 rule, what is the approximate percentage of cars that remain in service between 54 and 66 months?
Do not enter the percent symbol.
ans =
Click here to see answer by ikleyn(52788)

Question 1130236: Lauren is planning to raise her batting average. When she set up her weekly practice schedule, her batting average was 250. Lauren intends to increase her batting average by 5 each week. Find a pattern and write a formula that will give her expected batting average after n weeks.
a1 =
d=
Using the formula, how many weeks will Lauren need to practice if she expects to earn a batting average of 300?
Click here to see answer by mananth(16946)

Question 1146477: Jenny puts aside $20 at the end of each month for 3 years. How much will she have then of the investment earns 8.2% p.a., paid monthly?
Click here to see answer by mananth(16946)

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