C

1003020901

Level: 
C
Let there be vectors: \(\vec{a}=(1,3,-1)\), \(\vec{b}=(0,3,1)\), \(\vec{c}=(-1,2,2)\). Find \(\vec{a}\times\vec{b}\) and \(\left(\vec{a}\times\vec{b}\right)\cdot\vec{c}\).
\(\vec{a}\times\vec{b}=(6,-1,3), \left(\vec{a}\times\vec{b}\right)\cdot\vec{c}=-2\)
\(\vec{a}\times\vec{b}=8, \left(\vec{a}\times\vec{b}\right)\cdot\vec{c}=(-8,16,16)\)
\(\vec{a}\times\vec{b}=(-6,1,-3), \left(\vec{a}\times\vec{b}\right)\cdot\vec{c}=2\)
\(\vec{a}\times\vec{b}=\sqrt{46}, \left(\vec{a}\times\vec{b}\right)\cdot\vec{c}=2\)

9000154801

Level: 
C
There are six money transports through the Sherwood forest. Robin Hood knows that two of the transports are secured by soldiers. Find the respective probabilities that if Robin's band attacks two random transports, then none, one and both transports will be secured by the soldiers.
\(\frac{6} {15},\, \frac{8} {15},\, \frac{1} {15}\)
\(\frac{3} {9},\, \frac{5} {9},\, \frac{1} {9}\)
\(\frac{1} {3},\, \frac{2} {3},\, \frac{2} {3}\)
\(\frac{1} {2},\, \frac{1} {4},\, \frac{1} {4}\)

9000153901

Level: 
C
Find the number of ways how to distribute \(8\) identical balls among \(5\) persons so that each of them gets at least one ball.
\(\left({7\above 0.0pt 3}\right) = 35\)
\(5^{3} = 125\)
\(\left({12\above 0.0pt 5} \right) = 792\)
\(\left({12\above 0.0pt 8} \right) = 495\)