Question

Sumit throws two dice, one a common cube and the other a regular tetrahedron, the number on the lowest face being taken in the case of tetrahedron; then find the probability that the sum of the numbers appearing on the dice is $6$.

• A. $\frac{1}{5}$
• B. $\frac{1}{6}$
• C. $\frac{1}{7}$
• D. $\frac{1}{8}$

Answer 1

The correct option is B $\frac{1}{6}$

Faces of cube contain $1,2,3,4,5,6$

Faces of tetrahedron contain $1,2,3,4$.

Sum$=6$

$1$ on tetrahedron and $5$ on cube

$2$ on tetrahedron and $4$ on cube $3$ on tetrahedron and $3$ on cube

$4$ on tetrahedron and $2$ on cube

ie(2,4),(3,3),(4,2),(5,1),

Total combinations $=6\times 4$

probability $=\frac{4}{6\times 4}=\frac{1}{6}$