Math
posted by Kristen .
Set Q is defined as odd integers from 1 to 2000. How many ordered pairs (a,b) are there in set Q whereby a<b?

for any odd number (b), there are (b1)/2 odd numbers less than it.
check on that thinking. for b= 11, the odd numbers less are 1,3,5,7,9 or five. Yep, it works.
There are 1000 numbers for the choice of b, so there must be this number of ordered pairs:
Sum b=1 to 1999(0dd) of (b1)/2
Sum 1/2 (b1)= 1/2 sum b  1/2 sum
and see if you can sum those from 1 to 1999 
Thanks for responding, it really helped.
Respond to this Question
Similar Questions

math check
Posted by TchrWill on Thursday, July 14, 2005 at 5:44pm. 2.)The sum of four consecutive odd integers is 336. Set up an equation AND solve for all of the integers. Two ways to approach this. 336/4 = 84 making the 4 consecutive odd … 
math
Give your own example of a function using a set of at least 4 ordered pairs. The DOMAIN will be any four integers between 0 and +10. The RANGE will be any four integers between 12 and 5. 
8th grande transition algebra
well, i am doing a math crossword puzzle on linear equations. I really need some help. here are the questions: what is Ax+By+C called? 
math
Give your own example of a function using a set of at least 4 ordered pairs. The DOMAIN will be any four integers between 0 and +10. The RANGE will be any four integers between 12 and 5 
math
1. Cynthia used some of the ordered pairs from the set below to make a new set. {(4, –3), (–2, 5), (5, 4), (7, 2), (2, –7)} She wrote the domain of this set as {2, 4, 5}. Which ordered pairs from the original set did Cynthia … 
Math
The members of the Farrell family are Mona, the mother; Scott, the father; Kellie, Katie, Kristin, and Karen, the daughter ; and Kyle the son Consider the ordered pairs (x,y) where x is the mother of y. A.. List the ordered pairs in … 
Math
The members of the Farrell family are Mona, the mother; Scott, the father; Kellie, Katie, Kristin, and Karen, the daughter ; and Kyle the son Consider the ordered pairs (x,y) where x is the mother of y. A.. List the ordered pairs in … 
Math help!!!
The members of the Farrell family are Mona, the mother; Scott, the father; Kellie, Katie, Kristin, and Karen, the daughter ; and Kyle the son Consider the ordered pairs (x,y) where x is the mother of y. A.. List the ordered pairs in … 
Discrete Mathematics. Need Help
Let A be the set of all ordered pairs of positive integers and R be the relation defined on A where (a,b)R(c,d) means that ba=dc. a)Show that R is an equivalence relation. b)Find [(3, 5)] and [(7, 1)]. 
MATH PLEASE HELP I BEG
Cynthia used some of the ordered pairs from the set below to make a new set. {(4, –3), (–2, 5), (5, 4), (7, 2), (2, –7)} She wrote the domain of this set as {2, 4, 5}. Which ordered pairs from the original set did Cynthia use …