Place the digits $1$ to $9$ in the circles so that the sum of three numbers on each diameter equals $15$.

Find the value of $\mathrm{A}, \mathrm{B}, \mathrm{C}, \mathrm{D}$ and $\mathrm{E}$ to complete the number triangle given below:

Fill in the circles with the correct digits.

Fill in the blank squares with $2$-digit prime numbers so that the sum of the numbers in both the horizontal and vertical squares is $161$.

The numbers $1$ to $9$ have been arranged in a pattern of triangles so that the sum along each side of the triangle is $22$. Find another such arrangement of the numbers to make the totals equal.

The given figure shows a $3\times 3$ grid. Place the digits $0-9$ in squares such that the sum of each row and each column is different.

The given set of figures shows the same die from different angles. Which number should come in place of the question mark?