AMC Questions (1 Viewer)

[kurt.physics]

Spoiler

21. D 22. C 23. E 24. C 25. B 26. D 27. B 28. A 29. B 30. C

So where did you get these?

 

[Undermyskin]

I can answer!
Q1: this is simple by using similar triangle you can find the length of the hypotenuse is 40 for triangle "24". then let 40*4, you have 160.
Answer: C.

Q2: The reason you have Pi is because when turning around a corner, you still have to remain a distance of 2m from the nearest part of the wall.

From adding the lengths of all the wall, substract 4m due to our turn at the right angle, we can limit the answer to either B or D.

Now we need to find the angle at each vertex P, R and Q.
Pi - ^P
Pi - ^Q
Pi - ^R
3Pi - Pi/2 (We can use sum of interior angel in a quadrilateral is equal 2Pi)

Now we have 5Pi/2. To find the 'circumference', we need to 5Pi/2 * 2=5Pi

Thus the answer is B.

CAn you check?

 

[tacogym27101990]

I'm probably wrong, so if i am can someone explain it to me.
but in those official solutions
it says
.5*5*32=160
but it doesnt, it equals 80
is there something els eu have to do?
thanks

 

[kurt.physics]

Thanks