Practice Question

[Bserton]

Anyone know how to solve the question on the Marine study guide about the two planes that start off a carrier at a 60 degree angle and fly at a constant rate for 1200 miles....etc??????

 

[korndog]

Since they're going at the same speed and at a 60 degree angle, the third side of the triangle they make is also 1200. Dividing 1200 miles by 500 mph gives 2.4 hours.
Or, you could split the triangle in half and use the sine of 30 degrees (0.5) to find half the length of the distance between the two (600), and then double that to get 1200.

 

[Bserton]

Thanks! Any idea about the one with captains, 2nd, and first lts....AND....the triangle in the circle in the square.

You help is greatly appreciated!

 

[korndog]

That mess hall one is tricky. Set the ranks to simple variables (2LTs = x, 1LTs = y, CAPTs = z) so you get:
x + y = 30
x + z = 45
y + z = 35

Then you combine the equations together (keep variables on one side and numbers on the other):
2x + 2y + 2z = 110

Divide by 2:
x + y + z = 55 people in the mess hall

And for the triangle/square/circle problem, I just looked at it and thought angle COD looked more like a right angle than a 30 or 60 degree angle. Not exactly sure what the geometric proof is though...

 

[Bserton]

Thanks a ton! Hoe did you do on the test? Well I would assume.