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 571213: geometric mean between 99 and 44
Click here to see answer by mrjunecarlo1095@ymail.com(10)

Question 571213: geometric mean between 99 and 44
Click here to see answer by Theo(3458)

Question 571989: IN A PILE OF LOGS, EACH LAYER CONTAINS ONE MORE LOG THAN THE LAYER ABOVE,IN THE TOP LAYER CONTAINS JUST ONE LOG. IF THERE ARE 105 LOGS IN THE PILE, HOW MANY LAYERS ARE THERE?
Click here to see answer by htmentor(789)

Question 572482: 1(1!) + 2(2!) + 3(3!) + . . . + n(n!).
Find the sum of this series if n = 15.
Click here to see answer by richard1234(5390)

Question 572645: Use the Method of Finite Differences to find a function for the following sequences. 2.5, 6, 13.5, 25
Click here to see answer by Edwin McCravy(8901)

Question 572590: find the first 3 terms of a geometric progression whose sum is 42 and whose product is 512
Click here to see answer by htmentor(789)

Question 573170: the sum of the arithmetic series is equal to the product of these two quantities. true or false?

Click here to see answer by solver91311(16877)

Question 573364: What is the Nth equation of the following pattern?
Figure 1; 3 tiles
Figure 2; 5 tiles
figure 3; 7 tiles etc.
(and I know how the pattern grows, I just need to know what the equation is)
Click here to see answer by scott8148(6628)

Question 573745: For a given map, two-thirds of an inch represents 80 miles. Two cities are 200 miles apart. How far apart are they on the map?
Click here to see answer by checkley79(3050)

Question 574037: How many terms are there in a geometric sequence if 6 is the first term, 1/2 is the common ratio and 3/64 is the last term?
Click here to see answer by reviewermath(507)

Question 574501: 1+3+5+7+ . . . +99+101 = (?) Please show me the steps.
Click here to see answer by reviewermath(507)

Question 574587: Find the nth term of the sequence
1 2 5 10...

Click here to see answer by stanbon(57290)

Question 574584: Can someone plz help me. plz show me how to work this problem. adding the polynomials.
(1/8x^2 -1/4x -3/8) + (-1/2x^2 -1/4x -1/2)
Click here to see answer by stanbon(57290)

Question 574659: List the first three terms of an arithmatic sequence with a first term of 6 and a twentieth term of 63
Click here to see answer by bucky(2189)

Question 574789: The sum of the first three terms of a geometric series is 14 and the product of the first three terms of this series is 64.
1. So determine the ratio?
2.Show that there are two different series that satisfy the above conditions.

Click here to see answer by richard1234(5390)

Question 574479: Find the limits of the following sequence.
{2/4n+1}
Click here to see answer by richard1234(5390)

Question 575136: The ninth term of the arithmetic sequence is 1/6 ; the sixteenth term is 2 ½. Find the first term.
Click here to see answer by chana(69)

Question 576626: Find two sets of numbers whose some is 20 and whose product is 96
Click here to see answer by Alan3354(30993)

Question 577453: Find the eighth term of a sequence that has a first term of 12 and a common difference of 3. I don't get this at all.
Click here to see answer by stanbon(57290)

Question 577583: 1. If Carla can drive 400 miles on 28 gallons of gas, how many gallons of gas will she need to travel 1000 miles?
Click here to see answer by jim_thompson5910(28545)

Question 577591: Kathy stood on the middle rung of a ladder. She climbed up 5, down 3, up 8, and up 4 more to get to the top of the ladder. How many rungs are there in this ladder? I tried dividing but I am not real sure how to solve this.
Click here to see answer by ankor@dixie-net.com(15646)

Question 577920: How many terms are in the geometric sequence 8, 24, 72...648?
Click here to see answer by stanbon(57290)

Question 577920: How many terms are in the geometric sequence 8, 24, 72...648?
Click here to see answer by dfrazzetto(277)

Question 577782: In a three digit number , the hundreds digit , the tens digit and the units digit are in descending order and in Arithmetic progression . Each digit of the number is multiplied by the sum of the other 2 digits . The sum of all such results is A. B is the product of the tens digit and the sum of all the digits and A = (4/3)B . Find the number of such numbers ..

Options available are
a)4 b)3 c)2 d) More than 4
Click here to see answer by Edwin McCravy(8901)

Question 578370: Use the Maclaurin series of f(x) = e^x to verify that d/dx e^x = e^x.
Thank you!
Click here to see answer by Tatiana_Stebko(1326)

Question 578597: Does the number always have to be an even number each time to get a common difference in a arithmetic sequence?
Click here to see answer by KMST(1868)

Question 578862: Here is the sequence : 1/3 ; 1 ; 1/9 ; 4 ; 1/27 ; 7 ; 1/81;...
H e l p m e f i n d t h e n e x t t h r e e t e r m s i n t h e s e q u e n c e .
Click here to see answer by scott8148(6628)

Question 579908: Determine if the following series are convergent of divergent. If the series is geometric find the sum as well:
[(-1)^n +1] / sqr n (NOTE: +1 is separated from ^n)
at n =1 to infinity

Thank you so much!

Click here to see answer by KMST(1868)

Question 579910: Determine if the following series are convergent of divergent. If the series is geometric find the sum as well:
[cos(n*pi/3)] / n factorial
at n =1 to infinity

Thank you so much!

Click here to see answer by KMST(1868)

Question 579911: Find the limits of the sequences.
an= cos(n*pi /2)
Thank you so much!
Click here to see answer by KMST(1868)

Question 580605: If a student had walked 1km/hr faster, he would have taken 15 minutes less to walk 3 km. Find the rate at which he was walking.

Click here to see answer by dfrazzetto(277)

Question 581075: What is the value of 10/7b if b = 2/5?
Click here to see answer by rfer(12657)

Question 581369: d^2+15d+44
Click here to see answer by nerdybill(6958)

Question 581929: How would you x so that x, x+2, and x+3 are consecutive terms of a geometric sequence and find the common ratio r of the sequence.
Click here to see answer by stanbon(57290)

Question 582136: A laptop manufacturer finds that the average time it takes an employee to load a laptop with software is 35 minutes with a standard deviation 15 minutes. Suppose you take a random sample of 64 employees. The standard deviation of the sample mean is:
Click here to see answer by stanbon(57290)

Question 583269: I don't know what category this goes on(so I'm sorry but) I have a problem
Marria read 1/4 of her book on Monday and read the rest on Tuesday. She read 80 more pages on Tuesday and Monday. What was the total pages in Marria's book
Click here to see answer by josmiceli(9668)

Question 583543: what is the 10th,20th,and 30th terms of
1.)3,14,25,36,47
2.)25,38,51,64,77

Click here to see answer by Edwin McCravy(8901)

Question 583554: consider the sequence 2,5,26,677,...determine the recursive formula
Click here to see answer by KMST(1868)

Question 583785: i need to revise sequinces and algerbra for my test TOMMOROW and i cant find a good website for it. do you know any websites or anything to help me revise, by the way im in ks3. please help now thank you
Click here to see answer by Edwin McCravy(8901)

Question 583415: Can you help me figure out what the formula is in this pattern: 8,24,72,216 ? Example of formula:3n-3 N=the position of the number
Click here to see answer by KMST(1868)

Question 584195: What is the arithmetic mean between 85-95?
Click here to see answer by JBarnum(2044)

Question 584747: my car gets 18 miles/ gallon
if driving 194 miles, how many gallons of gas will i need
Click here to see answer by Edwin McCravy(8901)

Question 584818: My grade in a certain math class is determined by three tests. My highest test score will count for 50%
of my grade and my lowest for 20%; the "middle" test score will count for 30%. I must have a weighted
average of 60 in order to pass the class. If I have already earned scores of 70 on my first two tests,
what is the lowest score I can earn on the third test for which I will still pass the class?
Click here to see answer by richwmiller(9135)

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