NTSE Stage 2 SAT 2015 Question Paper

The given equation is
$2\mathrm{x}+\mathrm{y}=10$
∴ $\mathrm{x}+\left(\mathrm{x}+\mathrm{y}\right)=10$
Now x + y is maximum when x = 0
∴ The maximum value of x + y is 10.
Now $2\mathrm{x}+\mathrm{y}=10$
∴ $2\left(\mathrm{x}+\mathrm{y}\right)-\mathit{y}=10$
Now x + y is minimum when
$\mathrm{y}=0$
∴ The minimum value of $\mathrm{x}+\mathrm{y}$ is
$\frac{10}{2}=5$
∴ The sum of maximum and minimum values of $\left(\mathrm{x}+\mathrm{}\mathit{y}\right)$
$=10+5=15$
∴ Option (d) is correct