Mathametics?

Question

how long will it take a mile-long train going 20 miles per hour to get completely through a 2-mile-long tunnel?

please explain answers no comments

Answer 1

The way to answer the question is this, set up a ratio and cross multiply.

20/60 = 2/x

(So the former being, 20miles per hour, over 60 minutes. And after the equal sign, it is 2miles, over X minutes.)

20x = 60 x 2

20x - 120

Divide all by 20

6 minutes.

Answer 2

At 20 MPH, it takes 3 minutes to travel a mile.

The tunnel is 2 miles long, and the train is 1 mile long.

3 miles must be traveled to clear the tunnel with the rear of the train.

3 miles x 3 minutes equals 9 minutes.

It takes 9 minutes for the train to traverse the tunnel.

Answer 3

about one minute, at least i think it is one minute.

Answer 4

20 mph means 1 mile travelled in 3 minutes.(60/20)

Back of train in tunnel after 3 minutes, 'cos it's a mile long.

6 more mins to get back of train out of tunnel.(2 miles*3 mins)



IT TAKES 9 MINUTES.

NO COMMENTS!

Answer 5

it takes 60 minutes for the train to travel 20 miles or

60 Minutes = 20 Miles

so now divide it by 2 and you'll get:

6 Minutes = 2 Miles

but since its a mile long train. you have to travel another mile so now its this:

9 Minutes = 3 Miles.

It will take the train 9 minutes to travel completely through the 2-mile long tunnel....

Answer 6

ok. the distance is suppose to be 3miles. for the train is a mile long.

speed= distance/time taken

time taken = 20/3 =0.15hours

0.15hours=9min.

Answer 7

Three days and nine minutes counting the derailment.