







An enclosure for some remote control boats 
20171003 

Roberto pose la question : I am trying to build a "ring" for our remote control boats, using irrigation pipe.
I'd like to use full 20' long sticks for the long sides and use eight of what we call
45s, which are actually 135' fittings to make the six short sides. If I know the length
of the two long sides, what would be the formula to find the exact lengths of the short sides?
Thank you. Penny Nom lui répond. 





How far apart are the boats? 
20161213 

Halley pose la question : Two boats leave port at the same time. Boat A travels east at a speed of 12 km/hr. Boat B travels southwest at a speed of 14 km/hr. After two hours, how far apart are the boats? North is 0 degrees. How do I figure this out.
Thanks Penny Nom lui répond. 





Travelling upstream and downstream 
20161017 

Kathleen pose la question : It took a boat 2 hours to reach town A going upstream. The way back was 1h20 min. What is the speed of the boat in still water if the speed of the stream is 3 mph? Penny Nom lui répond. 





Travelling with and against he current 
20160209 

Lloyd pose la question : A boat travelled 210 miles downstream and back. The trip downstream took 10hrs, the trip back took 70hrs
1. what is the speed of the current?
2. what is the speed of the boat in still water? Penny Nom lui répond. 





A man a ship and a wharf 
20140926 

Ralph pose la question : A man om wharf 12 meters above the level of water is pulling a rope tide to a boat at the rate of 2 meters per minute. How fast is the boat approaching the wharf when there are 20 meters of the rope our. (with solution) Penny Nom lui répond. 





Two boats 
20111130 

Shayan pose la question : A boat is traveling 20 miles per hour when it passes a lighthouse.
another boat is traveling at 15 miles per hour when it passes a point.
the lighthouse and the point are 175 miles apart.
when will the boats pass each other? Penny Nom lui répond. 





What is the speed of the current? 
20100525 

tien pose la question : a boat travels upstream, against a current, at a speed of 4 miles per hour. On the return trip, the boat travels downstream, with the current , at 10 miles per hour. the speed of the current remains constant. what is the speed of the current? Penny Nom lui répond. 





Sammy and his motorboat 
20100511 

Jordan pose la question : Sammy owns a motorboat that travels 4 miles/hour in still water. It goes 12 miles upstream and 12 miles back again (downstream) in a total of 8 hours. Find the speed of the current of the river. Penny Nom lui répond. 





A question from a boat builder 
20100101 

Grant pose la question : I am a boat builder, trying to lay out shape of side's elevation.
My question is, how do I define the length of a circle's radius, if I know the chord length
(20 ft) and the segment of the radius between the chord and the circle is known (7 inches)? Penny Nom lui répond. 





How high is the ledge? 
20091003 

gabby pose la question : Standing on a ledge, there is a boat 25 degrees below you. The boat has a 1,000ft. tower. If the angle of elevation to the top of the tower is 15 degrees, how high is the ledge? Stephen La Rocque lui répond. 





Two Boats 
20090516 

Simon pose la question : Two boats, one travelling towards the east and the other travelling towards the north, are 10 km apart afetr an hour. If the speed of one boat is 2 more than the speed of the other boat, what is the speed of the faster boat? Stephen La Rocque lui répond. 





The path of a small sailboat 
20081119 

jane pose la question : a sailor in a small sailboat encounters shifting winds. she sails 2.00 km East
then 3.40 km North East, then an additional distance in an unknown direction. Her final position
is 6.68 km directly east of the starting point. find the magnitude & direction
of the third leg of the voyage. Harley Weston lui répond. 





How far are the boats apart? 
20081114 

dom pose la question : Two boats leave port at the same time. They leave at 150 degree angle. One boat travels at 10mph and the other at 20mph. After two hours how far are the boats apart? Penny Nom lui répond. 





The speed of the boat and the river 
20081028 

Jenn pose la question : On the Amazon River in Brazil, a boat goes 50 miles upstream in 3 hours, later the boat returns to the starting point in 2 hours. What is the speed of the boat in still water and what is the current speed in this part of the Amazon? Penny Nom lui répond. 





Angle of depression (declination) between sailboat observations 
20070718 

Joyce pose la question : From a cliff 150 ft above a lake, we see a boat sailing directly towards us.
The angle of depression of the boat is seen to be 5 degrees and 7 inches and
11 degrees and 18 inches. Find the distance sailed between observations. Stephen La Rocque lui répond. 





Velocity 
20070404 

Jessica pose la question : The speed of the current in a river is 2mph. Jessica travels 20 miles upstream and then 20 miles downstream in a total time of 5 1/3 hr. Find the speed of the boat.
I know you have to use V= d/t, but what is the equation for time because you have to factor in that upstream the boat is slower and downstream the boat is faster? Penny Nom lui répond. 





Boat trigonometry 
20070404 

Kimi pose la question : Hi,
I have been working on the attached math problem for my college trig class for over a week. Every avenue I've tried seems to lead either to a dead end, an unreasonable answer, or extremely complicated computations. I was able to calculate the speed of the boat to 3.51 mph, but cannot figure out the measure of angle beta. Once I can figure that out, I can do the rest of the problem.
Thanks,
Kimi Stephen La Rocque lui répond. 





What is the speed of the current? 
20070107 

Bob pose la question : A motorboat can maintain a constant speed of 16 miles per hour relative to the water. The boat makes a trip upstream to a certain point in 20 minutes; the return trip takes 15 minutes. What is the speed of the current? Haley Ess lui répond. 





Rate of a boat and a river 
20061209 

Dale pose la question : If a boat goes downstream 72 miles in 3 hours and upstream 60 miles in 6 hour, the rate of the river and the rate of the boat in still water respectively are ____? Stephen La Rocque lui répond. 





A boat is being pulled towards a dock. 
20061106 

Cassie pose la question : A boat is being pulled towards a dock. If the rope is being pulled in at 3 feet per second, how fast is the distance between the dock and the boat decreasing when it is 30 feet from the dock? Penny Nom lui répond. 





A boat travels 60 miles upstream ... 
20060528 

Teenarick pose la question : A boat travels 60 miles upstream against the current in 3 hours. It takes 2 hours for the return trip. Find the speed of the boat in still water. Penny Nom lui répond. 





A boat weighs 1500 lb more than its motor ... 
20051017 

Dimitri pose la question : A boat weighs 1500 lb more than its motor and 1900 lb more than its trailer. Together the boat and motor weigh five times as much as the trailer. How much does the boat weigh? Penny Nom lui répond. 





Two problems 
20050429 

Sara pose la question :
#1 A boat is traveling in a straight line across a river from point D, directly opposite town P, to a point Q, two thirds of the distance from town P to town R. Towns P and R are towns on the same side of the lake and are 18 miles apart. Line DQ passes through town S, which is 8 miles north of town R. Points P, Q, and R are collinear. What is the length of QS in Miles?
How many miles does the boat travel across the river?
#2 What is the area of a regular hexagon if the perimeter is 24cm?
Penny Nom lui répond. 





A boat travels 12 km upstream... 
20030903 

Sohaib pose la question : A boat travels 12 km upstream and back in 1 hour 45 minutes. If the speed of the current is 3km/hr throughout, find the speed of the boat in still water, giving your answerÝcorrect to 3 decimal places. Penny Nom lui répond. 





The volume of a fuel tank 
20030816 

Phil pose la question : I hope you can help me out with a small problem. My boat has a fuel tank measuring 1680mm long x 630mm wide x 130mm high. Can you tell me how much fuel it will hold in both litres and imperial gallons. Penny Nom lui répond. 





Joe and his dad 
20010828 

Sarah pose la question : Joe Spout left a campsite on a trip down the river in a canoe, traveling at 6 km/h. Four hours later, Joe's father set out after him in a motorboat. The motorboat traveled 30 km/h. How long after Joe`s father started did he overtake the canoe? How far had Joe traveled down the river when his father overtook him? Leeanne Boehm lui répond. 





The speed of the boat 
20010712 

Sharon pose la question : A motor boat is travelling in a southeasterly direction in water that is flowing from the south at 2km per hour. Show that the speed of the boat is (6 times the square root of 2) km per hour, given that it can travel at 10km per hour in still water. Penny Nom lui répond. 





Average speed 
20010501 

Tom pose la question : A ship goes in one direction, west to Hawaii, at 20 nautical miles per hour and, because of the wind, makes the return trip at 30 nautical miles per hour. What is the average speed? Claude Tardif lui répond. 





Two boats 
20010419 

Pat pose la question : Two boats head directly toward each other, one of them traveling 12 miles per hour and the other traveling 17 miles per hour. They begin at a distance of 20 miles from each other. How far apart are they one minute before they collide? Penny Nom lui répond. 





Two ferry boats 
20010325 

Gil pose la question : Two ferry boats leave from opposite shores. One is faster than the other. They meet 720 yards from the nearest shore. They proceed to destination and upon returning they meet 400 yards from the other shore. What is the exact width of the river. Penny Nom lui répond. 

