First compute the mean:
(4.67 + 4.98 + 4.34) / 3 = 4.66
then compute the variance:
(4.67-4.66)^2 = 0.0001
(4.98-4.66)^2 = 0.1024
(4.34-4.66)^2 = 0.1024
sum of the three = 0.2049
then take the square root:
= 0.452
the standard deviation is 0.452
Answer:
7.2hours
Step-by-step explanation:
5kg:12hrs
(divide both sides by 5)
1kg:2.4hrs
(multiply both sides by 3)
3kg:7.2hrs