Seemingly simple arc length problem I keep getting wrong

[1MileCrash]

Homework Statement

Suppose you are headed toward a plateau 60 m high. If the angle of elevation to the top of the plateau is 25*, how far away from the plateau are you in meters?

Homework Equations

S = (theta)r

The Attempt at a Solution

In my head this translates as I am given theta and arc length and must find radius.

Radius = (arc length) / (angle measure)

25* is roughly 0.436332313 radians, 60 divided by that is roughly 137.51.

The correct answer is 128.67.

Why?

 

[lanedance]

i think you want to use
sin(t) = opposite/hypotenuse

draw a picture to understand why

 

[HallsofIvy]

Why are you talking about "arclength" at all? There is no arc or circle in this problem. You have a right triangle with one angle of 25 degrees and one leg of length 60.

I would interpret "distance to the plateau" as meaning on the flat- the "near side" of this triangle, not the hypotenuse as lanedance seems to be doing.

 

[lanedance]

Fair bump as usual halls;)

 

[1MileCrash]

Well darn, it was given among a bunch of arc length problems so i just assumed.