Friday

November 28, 2014

November 28, 2014

Posted by **Steve** on Monday, November 30, 2009 at 4:47pm.

A boat leaves a dock at 9:00 P.M. and travels due south at a speed of 20 km/h. Another boat has been heading due east at 15 km/h and reaches the same dock at 10:00 P.M. How many minutes after 9:00 P.M. were the two boats closest together? Round your answer to the nearest minute.

An oil refinery is located on the north bank of a straight river that is 2 km wide. A pipeline is to be constructed from the refinery to storage tanks located on the south bank of the river 3 km east of the refinery. The cost of laying pipe is $300,000 per km over land to a point P on the north bank and $600,000 per km under the river to the tanks. To minimize the cost of the pipeline, how far from the refinery should P be located? (Give your answer correct to two decimal places.)

- Calculus -
**bobpursley**, Monday, November 30, 2009 at 4:59pmwrite the position of each boat as a function of time. Then, write the distance equation between those positions. Then, minimize.

On the second, make a diagram,going up the river L km, then across the river some distance. WRite the cost function as a function of L.

**Answer this Question**

**Related Questions**

calculus - a boat leaves a dock at 2:00 pm and travels due south at a speed of ...

calculus - Boat A leaves the dock at 12pm heading due South at a constant speed ...

Algebra 1 - A boat towing a water skier leaves a dock and travels east at a ...

Calculus Practice Problems - A boat is pulled into a dock by a rope attached to...

Calculus - At 2:00PM boat X is heading due west at 15mph towards a dock that is ...

calculus - A boat is pulled into a dock by a rope attached to the bow of the ...

Pre-Calculus-Trig - A boat travels for 8 kilometers in a straight line from the ...

Physics - A speed boat at rest begins to move in a straight line from a dock. ...

math - a boat leaves a dock at 2:00pm ,heading west at 15 km/h. another boat ...

calculus - A boat is pulled into a dock by a rope attached to the bow of the ...