Questions on Algebra: Sequences of numbers, series and how to sum them answered by real tutors!

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Question 513337: what is the number pattern 8,16,4,8,2need answer for the next two numbers thanks
Click here to see answer by scott8148(6628)

Question 513638: how to solve 3(2a-1)+5=14
Click here to see answer by nerdybill(6962)

Question 514512: find the 7th term of a sequence when rule is 2+2
find 4th rule when rule is n2-2
Click here to see answer by stanbon(57361)

Question 514575: Six times a number equals the sum of that number and negative 20. What is the number?
Click here to see answer by rfer(12662)

Question 514917: Could someone help to solve this question:
Dad wanted his car to be clean and shiny every day for a week to impress a customer of his. To hose and wipe down the car, he offered to pay his son James 15 cents the first day and double the daily payment each succeeding day thereafter. If James accepted the deal, how much money did he make?

$9.60 $12.40 $14.40 $16.20 $19.05 $38.25
Thank you for your help.
Click here to see answer by Maths68(1474)

Question 514934: The 17th term of an arithmetic progression is 81 and the 33th term is 145. Find a and d
a=first term
d=common difference
Click here to see answer by plover(15)

Question 515319: How do I find all numbers for which the rational expression is undefined? For this rational expression -(18)/(11y). Please help I am confused!
Click here to see answer by oberobic(2304)

Question 515703: I am a fraction whose product with seven is the same as my sum with seven.Who am I?
Click here to see answer by Alan3354(30993)

Question 516344: Use the Method of Finite Differences to find a function for the following sequences. Explain your process.
a. 9, 5, -5, -21, . . .
b. 2.5, 6, 13.5, 25, . . .
Ok...This is what I have done.
For "a" there is a second common difference of -6, and for "b" there is a second common difference of 4. Now I have forgotten how to use the method of finite differences. I remember learning something about generating the sequence by using:
a_n+1 = a_n + (the second common difference)n + something?
But I’m not sure this is what I need to use…I’m sure if I could just see “a” done I can do “b”. Thanks in advance for the help!

Click here to see answer by stanbon(57361)

Question 516669: algebraic expression for the Nth term 2, 4, 8, 16, 32, 64,
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Question 517096: what is the nth term for
10,17,24,31,38,
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Question 517313: 45 is 54% of what?
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Question 517315: 45 is 54% of what?
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Question 517484: Trying to understand this number pattern; Can you give me input? Thank you!
X Y
0 0
1 1
2 8
3 27
4 64
5 ___
6 ___
Click here to see answer by bucky(2189)

Question 519025: Find the odd one out
217, 343, 154, 231, 168, 294
Click here to see answer by syberlazer(5)

Question 519025: Find the odd one out
217, 343, 154, 231, 168, 294
Click here to see answer by solver91311(16897)

Question 519028: Which number comes next in this series? 1/64, 1/32, 1/16, 1/8, 1/4, 1/2, ?
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Question 519541: One number is 12 less than another number. Their product is -32. What is the least value the smaller number could be?
Click here to see answer by oberobic(2304)

Question 520369: OK. I have 6(t+w)to the second +11(t+w)-10
The book gives me this answer (3t+3w-2)(2t+2w+5)I can see where the numbers are from the original equation but I don't see how to get there. How would you determine that you would not use a (nx+b)(nx-c) format and you would have to use 3 numbers in each set?
Click here to see answer by solver91311(16897)

Question 520438: What is the sum of 1 1/4 + 0.8?
Click here to see answer by rfer(12662)

Question 520848: The first term of an A.P is 7 and the sum of the first 40 terms is 1216. Find the nth term, and the 20th term.
Click here to see answer by solver91311(16897)

Question 521102: the ratio of men to women is 3 to 4 and the ratio of americans to non americans is 7 to 2 if the number of people in the room is less than 100, how many people are in the room?
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Question 521167: expand: (x+3)^12
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Question 521172: expand:(x^2+y^2)^13
Click here to see answer by oberobic(2304)

Question 521188: hi i was wondering what the numerical pattern is for 7,19,31,43
Click here to see answer by oberobic(2304)

Question 521188: hi i was wondering what the numerical pattern is for 7,19,31,43
Click here to see answer by jim_thompson5910(28595)

Question 522593: please help me solve this challenge question on arithmetic sequences: if the 9th term of an arithmetic sequence is 27 and the 25th term is 123 what is the first term of the sequence
Click here to see answer by Maths68(1474)

Question 522654: how many numbers between 150 and 300 are divisible by 7?
Click here to see answer by Tatiana_Stebko(1326)

Question 523201: if every fourth trick-or-treater is a vampire, and every 6th, robot, how many of each will you see if seventy-five trick -or treaters come to your door?
Click here to see answer by stanbon(57361)

Question 523962: Norris currently has an account balance of $3,703.05. He opened the account 25 years ago with a deposit of $1,725.95. If the interest compounds monthly, what is the interest rate on the account?
Click here to see answer by Alan3354(30993)

Question 523976: 45=3y+15

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Question 524054: Find two numbers (exactly) whose product is 24 and whose sum is 21
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Question 524216: If a5= 48 and a17=196608 are he terms of a geometric sequence find a32.. Please help me solve this geometric sequence.
Click here to see answer by Maths68(1474)

Question 524498: The first term of a geometric sequence is 5 and the common ratio is 2. Find the first four terms of the sequence.
Click here to see answer by Edwin McCravy(8909)

Question 524497: Hi,
Could you help me find the 7th, 8th, and 9th terms of the following sequence
(1, 2, 3, 6, 11, 20, ...)? As the sequence progresses, each number equals the sum of the previous three numbers (ie 20 = 11 + 6 +3), but I can't figure out how they got 1 and 2. Another idea is that every even term equals the previous term plus 3 to increasing powers (3 to the zero is 1, 3 to the first is 3, etc-- sorry no exponents or superscript in the text box!)and every odd term is simply a summation. I'd really appreciate any help you can give.
Thanks very much,
Amy
Click here to see answer by richard1234(5390)

Question 524969: What is the next number in the sequence and why?
-1, 8, -56, 226, -1680
Click here to see answer by stanbon(57361)

Question 525207: I don't know what the topic should be haha(: but anyways, here is my question.
Simplify: -5(8-b)
I do not get how to do these type of problems at all, and the book just confuses me, thanks for your help!
Click here to see answer by lovefh8(1)

Question 525828: What is the mystery number x?
x has 3 digits
The tens digit is half the hundreds digits
The number is odd.
The sum of the digits is 9
Answer: x=
Click here to see answer by scott8148(6628)

Question 527391: 1 3 7 13 15 19 25 27 31 37 ____

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Question 527412:
Click here to see answer by oberobic(2304)

Question 528063: I have a table setup where the term number is; and the values are:
Term# Term Values
1, 1
2, 2
3, 4
4, 8
5, 16
6, 32
I need to find an algebraic equation to match the table. I thought of using 2^0 but I have no term# of zero. Is it possible to get an equation to this table as it is?
Click here to see answer by Alan3354(30993)

Question 528376: Provide an example of an arithmetic series which totals zero. Using complete sentences, explain how you created the example.

Click here to see answer by Edwin McCravy(8909)

Question 528423: six consecutive multiples of five add up to 765
Click here to see answer by Alan3354(30993)

Question 528657: What is the value of A+B if the A is the fist term and the B is the common difference of the sequence whose 4th term is 3 and 20th term is 35?
Click here to see answer by Maths68(1474)

Question 528662: What is the value of A+B if the A is the first term and B is the common difference of the sequence whose 4th term is 3 and 20th term is 35?
Click here to see answer by Maths68(1474)

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