MHB What is the Average Speed of a Train Traveling 18 km in 20 Minutes?

Click For Summary
The average speed of a train traveling 18 km in 20 minutes is calculated by converting the time into hours, resulting in 0.333 hours. Using the formula for average speed, v = d/t, the calculation yields an average speed of 54 kilometers per hour. The discussion emphasizes the importance of using fractions instead of decimals for clarity in calculations. Participants highlight that the recurring decimal can be avoided by using the fraction 1/3. Overall, the average speed determination is straightforward when using the correct time conversion.
mathlearn
Messages
331
Reaction score
0
The total distance traveled by trains is 18 km & the time spent is 20 minutes. Find the average speed of the train in kilometers per hour.

I' m stuck right in the beginning in converting 20 minutes to hours by dividing from 60 which I get this recurring decimal 0.33333
 
Mathematics news on Phys.org
You don't need a decimal value...

$$\overline{v}=\frac{d}{t}=\frac{18\text{ km}}{\dfrac{1}{3}\text{ hr}}=54\text{ kph}$$
 
MarkFL said:
You don't need a decimal value...

$$\overline{v}=\frac{d}{t}=\frac{18\text{ km}}{\dfrac{1}{3}\text{ hr}}=54\text{ kph}$$
Thanks :D The times when you got to decide between fractions and decimals
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

Similar threads

  • · Replies 8 ·
Replies
8
Views
3K
Replies
20
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
Replies
3
Views
904
Replies
10
Views
3K
Replies
6
Views
2K
  • · Replies 21 ·
Replies
21
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K