A car travels the first 19 km of its journey at an average speed of 57 km/h and the remaining
55 km at an average speed of 110 km/h. Find the
average speed of the car for its entire journey.

88.8km/h

Step-by-step explanation:

Since 19 is a third of 57 we divide 60 minutes  by 3 which is 20 to find how long it took to drive 19 km.

since 55 is half of 110 I divide 60 minute by 2 to find how long it took drive 55 km.

I add the total time i took to drive which is 50 min but i need to convert it to hours so i do 50/60 then i get the total distance driven (19+55)74km. After i get those i divide 74 by .833333333 which is:

74km/.8333333h=88.8

answer: all the values are within because it has a pattern that repeats from -6 to 4.

good luck!

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.