Competition results: Result 10 20 30 40 50 Participants 1 2 5 k 3 Mean value of the results is 34. $\displaystyle k=?$ Help?
Follow Math Help Forum on Facebook and Google+
If the mean value of the results is 34, then you need to solve the following for $\displaystyle k$: $\displaystyle \frac{1(10)+2(20)+5(30)+k(40)+3(50)}{1+2+5+k+3}=34$
The mean is equal to the sum of the results divided by the sum of the competitors, so: $\displaystyle \frac{10+20+30+40+50}{1+2+5+k+3}=34$ From there, it's simple algebra. Solve for k.
Originally Posted by downthesun01 The mean is equal to the sum of the results divided by the sum of the competitors, so: $\displaystyle \frac{10+20+30+40+50}{1+2+5+k+3}=34$ From there, it's simple algebra. Solve for k. cpbrunner's got it right. You have to take the frquencies into account on the numerator. downthesun01 hasn't.
My mistake. You're totally right
View Tag Cloud