Answer:
C
Step-by-step explanation:
Here in this question , we are interested in calculating the total distance covered by the train in the 10 minutes that it ran.
From the first part of the question, we already know the distances in the first 5 minutes.
Now, to calculate the total distance in the second 5 minutes, we use the distance formula since we have the average speed and the time;
Mathematically; Total distance = average speed * time
From the question, average speed is 33km/h, while time is 5 minutes. To achieve a consistent unit, we convert 5 minutes to hours.
That would be 5/60 = 1/12 hours
So the total distance in the second 5 minutes is;
33 * 1/12 = 2.75 km
Now, to calculate the total distance traveled, let’s add up the distances in the first 5 minutes and convert to kilometers;
That would be;
68 + 127 + 208 + 312 + 535 = 1,250 m
Let’s convert this to km.
We simply divide by 1000 = 1250/1000 = 1.25 km
The total distance is thus ;
1.25 + 2.75 = 4 km
Answer:
Mean age = 1271.27
Step-by-step explanation:
No of children = 77
The age at which children first began to combine words = 16.51 months
Mean age = No of children × age at which children first began to combine words
= 77 × 16.51
= 1271.27
Mean age = 1271.27
