1.
md= 60g, m.apa= 0,54 kg = 540 g
ms = md+m.apa = 60+540 = 600 g
c% = mdx100/ms = 60x100/600 = 10%
2.
ms= 750 g , c%= 25%
c%= mdx100/ms => md = msxc%/100
= 750x25/100 = 187,5 g
3.
md = 40g , c%= 15%
c%= mdx100/ms => ms = mdx100/c%
= 40x100/15 = 266,67 g