Central Angles and Inscribed Angles I

Project ID: 
6000000007
Accepted: 
SubArea: 
Type: 
Layout: 
Question: 
The figure shows the clocks along with the inscribed angles. Match each angle with its radian measure:
Question 1 Image: 
Answer 1: 
$\frac \pi 2$
Question 2 Image: 
Answer 2: 
$\frac \pi 4$
Question 3 Image: 
Answer 3: 
$\frac \pi 3$
Question 4 Image: 
Answer 4: 
$\frac {5\pi }{12}$
Question 5 Image: 
Answer 5: 

$\frac \pi 6$

Question 6 Image: 
Answer 6: 
$\frac \pi {12}$
Tex: 
% http://math4u.vsb.cz/ticket/31914 \newcommand\OBR[4][4mm]{ \obrMsr{-1.3,1.35,-1.3,1.35}[3cm,] { %\obrClip \footnotesize \obrKrizek {0,0}{below}{} \draw (0,0) circle (1); \foreach \i in {1,...,12} {\draw ({cos(90-(\i)*(360.0/12))},{sin(90-(\i)*(360.0/12))}) node {} coordinate (A\i);} \draw (A#2)--(A#3)--(A#4); \obrUhelB*[#1] {A#2}{A#3}[?]{A#4} \foreach \i in {1,...,12} {\draw ($1.27*(A\i)$) node {\colorbox{white}{\!\!${\i}$\!\!}};} \foreach \i in {1,...,12} {\draw ($1.025*(A\i)$) -- ($0.975*(A\i)$);} } } \otazka{\OBR 2{10}8}{$\frac \pi 2$} \otazka{\OBR 1{10}4}{$\frac \pi 4$} \otazka{\OBR 951}{$\frac \pi 3$} \otazka{\OBR 3{10}8}{$\frac {5\pi}{12}$} \otazka{\OBR[6mm] 5{10}7}{$\frac\pi 6$} \otazka{\OBR[10mm] 4{9}5}{$\frac \pi{12}$} \NastavOD{6} \def\preAnswers{\vspace*{-12pt}}