smc

The scale factors for the increases are $1+\frac{i}{100}$ and $1+\frac{j}{100}$, so the overall scale factor is $(1+\frac{i}{100})(1+\frac{j}{100})=1+\frac{i}{100}+\frac{j}{100}+\frac{ij}{100^2}$. To convert this to a percentage, we subtract 1 and then multiply by 100, giving $i+j+\frac{ij}{100}$, or $\boxed{(i+j+\frac{ij}{100})\%}$.