Given that R=130 and S=90. ST are congruent to UT so therefore U=90 and T=50
In order to obtain a standard deviation of 0, all members of the data set should be equal.
This means that each of the 100 members in the data set is equal to 50 (the mean value).
Answer:
The smallest observation in the set is 50.
C + t = 75......c = 75 - t
6c + 3t = 312
6(75 - t) + 3t = 312
450 - 6t + 3t = 312
-6t + 3t = 312 - 450
-3t = - 138
t = -138/-3
t = 46 <=== 46 cups of tea were sold
c = 75 - t
c = 75 - 46
c = 29 <=== 29 cups of coffee