# car

## 33-34 Time Rates: A car traveling east and airplane traveling north

## 31-32 Train in an elevated track and car in perpendicular road

**Problem 31**

An elevated train on a track 30 ft above the ground crosses a street at the rate of 20 ft/sec at the instant that a car, approaching at the rate of 30 ft/sec, is 40 ft up the street. Find how fast the train and the car separating 1 second later.

## 28-29 Time Rates: Two cars driving on roads that intersects at 60 degree

**Problem 28**

At noon a car drives from A (Fig. 48) toward C at 60 miles per hour. Another car starting from B at the same time drives toward A at 30 miles per hour. If AB = 42 miles, find when the cars will be nearest each other.

## 25 Two cars that may collide at 12:30 PM

**Problem 25**

One city *E*, is 20 miles north and 20 miles east of another city, *F*. At noon a car starts south from *E* at 40 mi/hr, at 12:10 PM, another car starts east from *F* at 60 mi/hr. Find the rate at which the cars approach each other between 12:10 PM and 12:30 PM. What happens at 12:30 PM?

## 22-24 One car from a city starts north, another car from nearby city starts east

**Problem 22**

One city C, is 30 miles north and 35 miles east from another city, D. At noon, a car starts north from C at 40 miles per hour, at 12:10 PM, another car starts east from D at 60 miles per hour. Find when the cars will be nearest together.

## 19-21 Two cars driving in parallel roads

**Problem 19**

One city A, is 30 mi north and 55 mi east of another city, B. At noon, a car starts west from A at 40 mi/hr, at 12:10 PM, another car starts east from B at 60 mi/hr. Find, in two ways, when the cars will be nearest together.