# Write a task of actions. from two cities removed from each other on 1680 km. there were at the same time towards each other 2 trains. The first train passes all this distance in 21 hour, and the second train in 28 hours in how many hours of the train will meet

Look

97

We learn speeds of trains 1) 1680:21=80km/h the speed of 1 train 2) 1680:28=60km/h speed 2 trains 3) 80+60=140km/h the speed of rapprochement 4) 1680:140=12ch the answer of 12 h

77

Answer add
McKinney David

### Other questions in the section - maths

Domnin

Straight lines of MN CD EF are crossed in a point of O AOE=55

2020-10-18 04:24:39

Semyon

1 7/9 + 3 4/9 4 5/13 + 2 9/13 9 - 3 11/13

2020-10-18 04:24:39

Dalatus

In northern Kazakstan 600 lakes, in the neighborhood of Kokshetau v2 are less than

2020-10-18 04:24:39

Makarovich

Help to solve please a column 892:4 580:5 954:3 678:6 798:7 408:8 567:7 330:6

2020-10-18 04:24:39

Lev

One city at the same time in opposite directions was left by the bus

2020-10-18 04:24:39