Answered

IDNStudy.com, ang iyong destinasyon para sa mga sagot ng eksperto. Ang aming platform ng tanong at sagot ay idinisenyo upang magbigay ng mabilis at eksaktong sagot sa lahat ng iyong mga tanong.

find the sum of all the integer multiples of 8 between 9 and 199.


Sagot :

[tex]S_n = \frac{n}{2}(a_1+a_n)[/tex]

[tex]a_1=16 [/tex]  since it is the first multiple of 8 after 9.
[tex]a_n = 192[/tex]  since it is the last multiple of 8 before 199.
n = 23  because there are a total of 23 multiples of 8 between 9 and 199.

[tex]S_{23} = \frac{23}{2}(16+192)=\frac{23}{2}(208)=23(104)=\boxed{2392}[/tex]

Therefore, the sum of all he integer multiples of 8 between 9 and 199 is 2,392.