0
How do you find the sum of all the integer multiples of 7 from 7 to 700?
Wiki User
∙ 13y ago
∑7n from n = 1 to n = 100 is a shorthand method of writing :-
7x1 + 7x2 + 7x3 +...........+ 7x 99 + 7x100
This can be written as 7(1 + 2 + 3 +........+ 99 + 100)
The sum (S) of a range of numbers from 1 to n is given by the formula S = 1/2 n(n + 1)
And substituting the relevant numbers gives, S = 1/2 x 100 x 101 = 5050
But this now needs multiplying by 7 to give the sum of the multiples = 7 x 5050 = 35350.
Wiki User
∙ 13y ago
Add your answer:
Earn +20 pts
What are all the multiples of 21?
There are infinitely many multiples of 21 and it is impossible to list them all other than as 21*n where n is an integer.
What is the multiple of 41?
There are infinitely many multiples. They are all of the form 41*k where k is any integer.There are infinitely many multiples. They are all of the form 41*k where k is any integer.There are infinitely many multiples. They are all of the form 41*k where k is any integer.There are infinitely many multiples. They are all of the form 41*k where k is any integer.
Are all multiples of 8 also multiples of 4?
Yes. By definition a multiple of 8 is any number that can be expressed as 8*n, where n is an integer. But 8n=4*(2*n), and 2*n is an integer, when n is an integer. Because 8n equals four times an integer, 8n is a multiple of 4.
What is the Find all the magic multiples of 9 from 1 to 100?
I don't know about "magic" in this context. Multiples are the number 9, multiplied by an integer, for example: 0 x 9 = 0 1 x 9 = 9 2 x 9 = 18 etc. If you just keep adding 9 at a time, you will get all the multiples.
What are common multiples of 512 and 648?
They are all the numbers in the set {41472*k, where k is an integer}.
What are multiples of 700?
Any multiple of 700. 700, 1400, 2100 and so on...
What is the set of all multiples of 3?
Z3 = {3n | n is an integer}
What are the integer numbers with the divisor 18?
18 and all the multiples of 18.
What are all the multiples of 21?
There are infinitely many multiples of 21 and it is impossible to list them all other than as 21*n where n is an integer.
What is all the multiples of 5?
There are infinitely many multiples of 5 so it is not possible to list them. They are all of the form 5*k where k is an integer.
What are the common multiples for 8 and 22?
Least common multiple is 88. Other multiples are 176, 264, 352, etc. and all integer multiples of 88.
List all 5 multiples of 10?
There are infinitely many multiples of 10 so it is far from clear what you mean by "all 5" multiples. Any integer which ends in a 0 is a multiple of 10.
What are common multiples of 32 and eight?
All multiples of 32 are also multiples of 8.
What is the multiple of 41?
There are infinitely many multiples. They are all of the form 41*k where k is any integer.There are infinitely many multiples. They are all of the form 41*k where k is any integer.There are infinitely many multiples. They are all of the form 41*k where k is any integer.There are infinitely many multiples. They are all of the form 41*k where k is any integer.
Are all multiples of 8 also multiples of 4?
Yes. By definition a multiple of 8 is any number that can be expressed as 8*n, where n is an integer. But 8n=4*(2*n), and 2*n is an integer, when n is an integer. Because 8n equals four times an integer, 8n is a multiple of 4.
Common multiples of 5 and 8?
They are all integers of the form 40*k where k is an integer.
What are the multiples of 23 8 and 12?
All numbers of the form 552*k where k is an integer.
