An airlines records show that its flights between two cities arrive on the average 5.4 minutes late with a standard deviation of 1.4 minutes. at least what percentage of its flights between the two cities arrive anywhere between

Interval between 2.6 minutes late and 8.2 minutes late is within 2 standard deviations of the mean (k =8.2â’5.4/1.4 =5.4â’2.6/1.4 = 2). By Chebyshev’s Theorem, at least 1 â’1/2^2 =3/4 of all flights, i.e. at least 75% of all flights arrive anywhere between 2.6 minutes late and 8.2 minutes late.

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm