3/5 of the T-shirts of the shop are on sale
5/8 of those on sale are blue
1/3 of the blue shirts on sale are medium size.
First calculate how many of the shirts on sale are blue:
[tex]\frac{5}{8}\frac{\div3}{5}=\frac{5}{8}\cdot\frac{5}{3}=\frac{25}{24}[/tex]25/24 of the shirts on sale are blue
Then divide that number by three to know how many are medium size:
[tex]\frac{25}{24}\div3=\frac{25}{72}[/tex]25/72 are blue and medium size
