Number operations?

Dec 2013
18
0
If the sum of all integers from 1 to 1,000,
inclusive, is x, then which expression
represents the sum of all integers from
1 to 998, inclusive?

(A) x – 1,999
(B) x – 999
(C) x + 999
(D) x + 1,999
 

Denis

Math Team
Oct 2011
14,592
1,026
Ottawa Ontario, Canada
Are you serious?
 
Jan 2014
30
0
MS, USA
Rfeynman16 said:
If the sum of all integers from 1 to 1,000,
inclusive, is x, then which expression
represents the sum of all integers from
1 to 998, inclusive?

(A) x – 1,999
(B) x – 999
(C) x + 999
(D) x + 1,999
Very Simple. And very mean on your part Denis. Not sure how you are a super user.

Anyway,

We begin with the given statement that the sum of all integers from 1 to 1000 is x, inclusive. Now then this includes numbers 1, 999, and 1000. However in the question we are only asked 1 to 998. This excludes 1000 and 999. Since x is the sum of the numbers INCLUDING 1000 and 999 we need to remove these from our solution. So we should take the sum of 1000 and 999, which gives us 1999. Now since x is the sum of those numbers, but we do not want them in our solution...so we should subtract 1999 from x. This will give us the solution, A.

Hope this helped! :) :)
________________________________________________________________________________________________________________________________________________

Impossible is just a word that quitters say to make them feel better about themselves.
 

mathbalarka

Math Team
Mar 2012
3,871
86
India, West Bengal
Cyriak said:
And very mean on your part Denis.
We usually prefer users to provide effort along with the question. This is not a homework help forum, I believe what Denis said is appropriate -- OP's intention was to dump a lot of question and expect us to provide answers. This is not what we do.

Cyriak said:
Not sure how you are a super user.
Staffs here decide which of us would become super user or not, it is inappropriate for you to question on staff decisions.
 
Jan 2014
30
0
MS, USA
We usually prefer users to provide effort along with the question. This is not a homework help forum, I believe what Denis said is appropriate -- OP's intention was to dump a lot of question and expect us to provide answers. This is not what we do.



Staffs here decide which of us would become super user or not, it is inappropriate for you to question on staff decisions.
The title of the forum is literally - High school math/Homework help. Are you sure you should be on the math team?
 

skeeter

Math Team
Jul 2011
3,360
1,850
Texas
The title of the forum is literally - High school math/Homework help. Are you sure you should be on the math team?
FYI, if you hover over the user name below his avatar, you'll see that mathbalarka hasn't been active on this forum since September 2015.
 
  • Like
Reactions: topsquark
Jan 2014
30
0
MS, USA
I never forget, I never forgive :)