The answer to the question you are asking is C
Answer:
6-hours
D = C + T
Step-by-step explanation:
The following equations represent the total distance travelled by each vehicle, the truck (C) and the Train (T) where x is the amount of time travelling in hours...
C = 45x
T = 60x
Since the truck traveled 2 hours longer than the train we can add this value to the variable x in the truck's distance equation and then make both equations equal one another to calculate the number of hours before they cover the same distance...
45(x+2) = 60x ... distribute 45 evenly
45x + 90 = 60x ... subtract 45x from both sides
90 = 15x ... divide both sides by 15
6 = x
Finally, we can see that both vehicles would have traveled the same distance at the 6-hour mark. Now to calculate the total distance traveled (D) we can use the following equation...
D = C + T
Ratio of classes A, B, C = 4 : 6 : 5, respectively
4 + 6 + 5 = 15
So, class A represents 4/15 of the TOTAL population
Class B represents 6/15 of the TOTAL population
Class C represents 5/15 of the TOTAL population
So, weighted average of 3 groups combined = (4/15)(65) + (6/15)(80) + (5/15)(77)
= 260/15 + 480/15 + 385/15
= 1125/15
= 75
Answer: B
Answer:
they are congruent
Step-by-step explanation:
they have the same points