[tex]Total\ price\ of\ all\ items:\\\\
skirt+blouse=60+40=100\$\\\\
SKIRT's discount:\\\\
40\%=0,4\\\\
0,4*60=24\$\\\\BLOUSE's discount:\\\\
20\%=0,2\\\\
0,2*40=8\$\\\\
Total\ discount:\\8+24=32\$\\\\
Percentage\ of\ total\ discount:\\\\
\frac{32}{100}*100\%=32\%[/tex]