







Gauss' Addition of whole numbers. 
20180430 

Brad pose la question : I found this on your site. Question: what is the sum of the first 100 whole numbers??
Is there a different formula if the numbers begin at a number other than one? For example
What is the series I want to add is goes from 7  53? Harley Weston lui répond. 





An arithmetic sequence 
20171130 

yo pose la question : x; 2x+1; 11 are three consecutive terms of an arithmetic sequence.calculate x Penny Nom lui répond. 





An arithmetic sequence 
20170717 

abbi pose la question : hi there im a student in 11 grade
ive been trying to do this task but i have no idea how to do it
the question is
Find the common difference and the n^th term of the arithmetic sequence if the first term is 4 and the twentieth sum of the terms is 1030 Penny Nom lui répond. 





Which term of this sequence has value 8? 
20160720 

Lauren pose la question : Hi there
Which term in the sequence 2; 5/3; 4/3 ; 1; ... has a value of 8.
Since term 2 and 3 of this sequence contain fractions which can be converted to recurring decimals. What is the best way to work out the common difference here.
I do however understand that to work out the nth term of an arithmetic series, the following formula Tn = a + (n1)d. In this series a = 2 Penny Nom lui répond. 





A sequence 
20160105 

Mia pose la question : the next three terms in each sequence. 0.4, 0.54, 0.68, 0.82, Penny Nom lui répond. 





The sum of the first 50 terms of an arithmetic progression 
20140726 

Joshua pose la question : Hello ...my is Joshua...I'm a grade 11 student...I got a question
Calculate the sum of the first 50 terms of an arithmetic progression: 112:98:84 Penny Nom lui répond. 





9,4,6,8,3,... 
20140331 

Alynna pose la question : You are given the following pattern: 9,4,6,8,3,...
Create a formula for the nth figure.
I have trouble finding the formula, I need help trying to find it. Penny Nom lui répond. 





An arithmetic sequence 
20140320 

Xabiso pose la question : The 10th term of an arithmetic sequence is 28 and the 7th term is 19. Calculate the common difference and the first term of the sequence. Penny Nom lui répond. 





An arithmetic sequence 
20140106 

paris pose la question : find the twentyfifth term of an arithmetic sequence whose first term is 12 and whose common difference is 6 Penny Nom lui répond. 





An arithmetic progression 
20120822 

A student pose la question : the 3rd term of an A.PPP is 10 more than the first term while the 5th term is 15 more than the second.find the sum of the 8th and 15th terms if the 7th term is 7 times the first term. Penny Nom lui répond. 





Three consecutive terms of an arithmetic sequence 
20111030 

Juliette pose la question : Find X when x, 1/2x + 7, 3x 1 are consecutive terms of an arithmetic sequence. Penny Nom lui répond. 





4 + 10 + · · · + (6n − 2) 
20100421 

Lan pose la question : Find the sum 4 + 10 + · · · + (6n − 2). The answer is 3(n^2) + n. How? Penny Nom lui répond. 





How many terms are there in this sequence? 
20090928 

tabby pose la question : How many terms are there in this sequence?
5,1,3,...,111 Penny Nom lui répond. 





The middle term of an arithmetic sequence 
20081215 

Leigh pose la question : Find the sum of the first fifteen terms of an arithmetic series if the middle term is 92 Penny Nom lui répond. 





How many terms in this sequence? 
20070611 

Jesse pose la question : How do I find how many terms are in the sequence? 51, 48, 45, ...., 75 Stephen La Rocque and Penny Nom lui répond. 





Arithmetic Series 
20070218 

Krista pose la question : Question The sum of the first 4 terms of an arithmetic series is 8 and the sum of the first 5 terms is 500. Determine the sum of the 3 terms. Stephen La Rocque lui répond. 





5,8,11,14,17 
20070118 

Mairead pose la question : the sequence i was given was 5,8,11,14,17 what is the nth term and what is the 10th term ? Paul Betts lui répond. 





The sum of 2000 consecutive integers is 1000 
20061029 

Matias pose la question : if the sum of 2000 consecutive integers is 1000, then the sum digits of the greatest of these 2000 integers is? Penny Nom lui répond. 





Arithmetic and Geometric Sequences 
20060419 

Skye pose la question : If the 1st, 4th, and 8th terms of an arithmetic sequence are consecutive terms in a geometric sequence, find the common ratio of the geometric sequence. Stephen La Rocque lui répond. 





An Arithmetic sequence 
20051201 

Aana pose la question :
The first term in an arihmetic series is 25 and the 3rd term is 19. Find the number of terms in the series if its is 82.
Here's what I did to find d
a+2d=19; 25+2d= 19 ;1925=2d d=6/2=3
This is where I'm stuck. Can you please provide me with some guidance.
Penny Nom lui répond. 





An arithmetic progression 
20041224 

A student pose la question : the 4th and 5th term of an arithmetic progration 47 and 52 respactively find
a)d
b)a1
c)a50 Penny Nom lui répond. 





The sum of 4,0,4..., 156 
20040428 

Christina pose la question : find the requested sum of the arithmetic sequence
4,0,4..., 156 Penny Nom lui répond. 





Finite differences 
20030210 

Jenny pose la question :
I need to find a formula that will work with any number. I am finding the volume of a 3d cross shape. Here are my results so far:
Term Number 0 1 2 3 4 5
nth term 1 7 25 63 129 231
1rst diff 6 18 38 66 102
2nd diff 12 20 28 36
3rd diff 8 8 8
I can't seem to find a formula that will work with any number. Any help would be much appreciated. Penny Nom lui répond. 





The sum of the first 1000 even integers 
20030206 

Jill pose la question : What is the sum of the first 1000 even integers? Paul Betts lui répond. 





Arithmitic sequence 
20030201 

A student pose la question : I am having problems solving this arithmetic sequence... 1, 5, 10, ___, 50, 1.00, ___, 10.00, ... I believe the answers to be 25 and 5.00 but I can't figure why. Claude Tardif lui répond. 





Arithmetic sequences 
20010910 

Rachel pose la question : I can't seem to figure out a problem that deals with arithmetic sequencing. This is the question: The 5th term in an arithmetic sequence is 1/2, and the 20th term is 7/8. Find the first three terms of the sequence. I attempted this problem with the formula: An = a + (n1)d (where the n represents the nth term, a is the first term, and d represents the common difference) I keep getting 9.5 for the first number, and then 3/120 as the common difference between the numbers. But as I have figured it, the sequence is getting greater and greater, and my data does not go with the terms given. Penny Nom lui répond. 





Geometric and arithmetic sequences 
20010126 

Garry pose la question : what are the equations for geometric and arithmetic sequences? also, what are the equations for finding the sums of those series? Leeanne Boehm and Penny Nom lui répond. 





The sum of the squares of 13 consecutive positive integers 
20000825 

Wallace pose la question : Prove that it is not possible to have the sum of the squares of 13 consecutive positive integers be a square. Harley Weston lui répond. 





The number of seats in an auditorium 
20000516 

David Evaska pose la question : There are 10 students in the first row of seats in an auditorium 12 in the second 14 in the third and 2 additional in each seat. The total number of rows is 40. I know the answer is 1960 can you please show me the formula step by step. Penny Nom lui répond. 





Sequences and series 
19980527 

Michael Le Francois pose la question : The sum of the first ten terms of an arithmetic series is 100 and the first term is 1. Find the 10th term. The common ratio in a certain geometric sequence is r=0.2 and the sum of the first four terms is 1248 find the first term. Penny Nom lui répond. 

