use gauss to find the sum of 4+8+12+...+800

Question

campbell_st · Answer

simply add the 1st and last term together

multiply by the number of terms 

then halve the answer... 

if you list the terms 

then below reverse the order and list the terms
and add the 2 lists together... you always get the same number



        4     8     12   16 .....      800
+   800 796  792  788 ....          4
------------------------------
    804  804  804   804            804

so multiply by the number of terms... 

and because you have 2 lists of the same pattern... you need to 
divide by 2 to get the sum of 1 list

anonymous · Answer

how would I do that? my teacher gave us the answers but wants us to figure out how to solve it. we dont do notes and do not have a book

campbell_st · Answer

well is 804 * 200... get that answer 

then halve it...

anonymous · Answer

Use the appropriate formula to find the indicated figurate number. the 19th triangular number

campbell_st · Answer

well the trianglular numbers are 

1, 3, 6, 10, 15, 21, ...

anonymous · Answer

I know the answer but i dont know how to solve it

anonymous · Answer

my teacher gives us the answers but tells us to solve it. But i have never heard of this stuff before

campbell_st · Answer

so do you know the formula for generating the numbers..?