Question : If the six-digit number 5x2y6z is divisible by 7, 11 and 13, then the value of $(x-y+3 z)$ is:

Option 1: 7

Option 2: 4

Option 3: 0

Option 4: 9

Question : If $x+y+z=13,x^2+y^2+z^2=133$ and $x^3+y^3+z^3=847$, then the value of $\sqrt[3]{x y z}$ is:

Option 1: $8$

Option 2: $7$

Option 3: $-9$

Option 4: $-6$

Question : If the 9-digit number $72 x 8431y 4$ is divisible by 36, what is the value of $(\frac{x}{y}-\frac{y}{x})$ for the smallest possible value of $y$, given that $x$ and $y$ are natural numbers?

Option 1: $1 \frac{5}{7}$

Option 2: $2 \frac{1}{10}$

Option 3: $1 \frac{2}{5}$

Option 4: $2 \frac{9}{10}$

Question : What is $\frac{\left (x^{2}-y^{2} \right)^{3}+\left (y^{2}-z^{2} \right )^{3}+\left (z^{2}-x^{2} \right )^{3}}{\left (x-y \right)^{3}+\left (y-z \right )^{3}+\left (z-x \right)^{3}}?$

Option 1: $\frac{(x+y)(y+z)}{(x+z)}$

Option 2: $(x+y)^3(y+z)^3(z+x)^3$

Option 3: $(x+y)(y+z)(z+x)$

Option 4: $(x+y)(y+z)$

Question : If a 4-digit number x58y is exactly divisible by 9, then the least value of (x + y) is:

Option 1: 4

Option 2: 5

Option 3: 3

Option 4: 2