Answer:
Step-by-step explanation:
Given are 3 data sets with values as:
(i) 8 9 10 11 12 ... Mean =10
(ii) 7 9 10 11 13 ... Mean =10
(iii) 7 8 10 12 13 ... Mean =10
We see that data set shows mean deviations as
(i) -2 -1 0 1 2
(ii) -3 -1 0 1 3
(iii) -3 -2 0 2 3
Since variance is the square of std deviation, we find that std deviation is larger when variance is larger.
Variance is the sum of squares of (x-mean). Whenever x-mean increases variance increases and also std deviation.
Hence we find that without calculations also (i) has least std dev followed by (ii) and then (iii)
(i) (ii) (iii) is the order.
b) Between (i) and (ii) we find that 3 entries are the same and 2 entries differ thus increasing square by 9-4 twice. But between (ii) and (iii) we find that
increase in square value would be 4-1 twice. Obviously the latter is less.
19.
A) 84 : 120 --) 7 : 10, I came up with it by knowing x, # of times ordered,
7(x) : 3(x) sum will be 120 and guessed from there.
B) Well I came up with it trying to get the ratio for A, 84 smoothies.
C) 84 ( smoothies) - 36 ( juice drinks)
20.
A) Ok you first have the birds from the first hour which sum up to 24. Then to calculate what of how many birds you saw for the second hour you use the ratio 2 (cardinals) : 3 ( chickadees) : 3 ( pigeons). Now before you use the ratio you need to know how many birds out of the 36 have not been seen in the first hour so just subtract 36 - 24 = 12. Next you figure out what number you can multiply every bird against to get a sum of 12 birds in total. I figured out it's 1.5 as a multiplier. I know physically it's not possible, but I did all the steps correct and apparently they don't care it's not realistic. I hope this helps you on the homework sheet.
Answer:
a = 16
Step-by-step explanation:
4/8= 1/2
you have to what 8 is half of
8×2= 16
a=16