Find the reduced form of the ratio of the first quantity to second quantity.
$$5 litre, 2500 ml$$
$$5$$ Liter = $$5000mL$$ (1L= $$1000mL$$)
$$\therefore$$ $$5$$ litre : $$2500$$ mL = $$5000mL:2500 \ mL$$$$=\frac{5000}{2500}=\frac{5000\div2500}{2500\div2500}=\frac{2}{1}=2:1$$
(HCF of $$5000$$ and $$2500=2500$$)