SOLUTION: (1+2+3+...+19)20 ----------- ----------- ----- = (21+22+23+...+39)40 Find 3 (n)s

Question 1006529: (1+2+3+...+19)20
----------------------------- =
(21+22+23+...+39)40

Find 3 (n)s

Answer by ikleyn(52781) (Show Source): You can put this solution on YOUR website!
.
What to find ?

-------------------------------------------------------------
Comment from student: simplify it into an expression using n
-------------------------------------------------------------

OK. (Why do not write it from the very beginning?)

The sum in the numerator is the sum of first 19 terms of an arithmetic progression 1, 2, 3, . . . , 19

S = 1 + 2 + 3 + . . . + 19 = = = 10*19.

The sum in the numerator is the sum of first 19 terms of an arithmetic progression 21, 22, 23, . . . , 39

T = 21 + 22 + 23 + . . . + 39 = = = 30*19.

Hence, the ratio you are asking for, is

= = = .

RELATED QUESTIONS
compute a one-sample t-test comparing the age of your sample to the age of the general... (answered by ikleyn)

convert each subject's age and height into a z-score. Using the z-score of �1.645 for... (answered by ikleyn)

What are the answers to all of these questions? 1. -6k+7k 2. 12r-8-12 3.... (answered by Fombitz)

Using Minitab Express, compute a one-sample t-test comparing the age of your sample to... (answered by greenestamps)

In the frequency distribution below,y represents age on last birthday for 40 people. Find (answered by rfer)

if 21^3 + 23^3= 21428, then 20*21*22 +... (answered by checkley79)

MAT 145: Topics In Contemporary Math QUESTION 12 Convert the message (answered by ikleyn)

MAT 145: Topics In Contemporary Math QUESTION 12 Convert the message... (answered by greenestamps)

ID Sex Ethnicity Age Car Type of info Stresslevel Stressscore (answered by ikleyn)