Answer:
16 : 3
Explanation:
both quantities must have the same units, so
£4 = 400p
then
£4 : 75p
= 400p : 75p
= 400 : 75 ( divide both parts by 25 )
= 16 : 3 ← in simplest form
the ratio is in simplest form when to other factor but 1 divides into both parts of the ratio.