In 2018, if the country of Serbia had imports of $10.58 billion and had an unfavorable balance of trade. This means that Serbia had?

Serbia had less than $10.58 billion in exports

Explanation:

Given that

Imports = $10.58 billion

Unfavourable balance of trade (or trade deficit) refers to the difference between the value of a country's exports and the value of its imports such that imports exceed exports.

Mathematical,

Trade deficit (T) = Import (I) - Export (E)

Make E the subject of formula

E = I - T

By substituton

E = $10.58 billion - T

From the above mathematical expressions, this means that value of export is less than $10.58 billion.

So, it's reasonable to conclude that Serbia had less than $10.58 billion in exports

In 2018, if the country of Serbia had imports of $10.58 billion and had an unfavorable balance of trade. This means that Serbia had export less.

Explanation:

The trade of balance deals with exports and import goods.

Trade Balance = Exports - Imports.

As mentioned above formula the trades balance would be more if the export goods ratio is higher than the imported goods.