A paint manufacturer wished to compare the drying times of two different types of paint. independent simple random samples of 11 cans of type a and 9 cans of type b were selected and applied to similar surfaces. the drying times, in hours, were recorded. the summary statistics are as follows. determine a 98% confidence interval for the difference, between the mean drying time for type a and the mean drying time for type

b. 4.25 to 15.35 hours 4.48 to 15.12 hours 4.18 to 15.42 hours 4.32 to 15.28 hours

solution:

the given function is ,

      =

the three roots of this quadratic function is , 0 ,8 and 10.all the roots are real and rational.

if a quadratic equation is of the form ,

sum of the roots = a + b +c= 0+8+10=18=  

product of roots taken two at a time = a b + b c+ c a = 0+80+0=80 =  

product of roots = a b c = 0=  

there are 11 doors in a hall starting from 0 to 11.the entry in the hall is permitted through gate number 0 and exit is allowed through only gate number 8 and 10.so, three roots(0,8,10) of quadratic function is given by entry and exit route of this hall.

a ≈ 172.05

step-by-step explanation:

the pictures.