Can you explain how does the answer shown in the picture below answers the question?

Assume that Home and Foreign produce only two goods-Cars and TVs. Home has 400 units of labour available. In Home, the unit labour requirement in car production is 40 and in TV production it is 20. On the other hand, Foreign has 450 units of labour available. Foreign's unit labour requirement in car production is 75, while in TVproduction it is 15.

a.Show that both Home and Foreign gain from trade. [3 points]

Note: the equilibrium relative price is 3.

Home without trade , it can use one hour of labour to produce / aTV = 120 TUS It can use one hour of labour to produce lac= 140 cars with trade . Home can sell : 14 cars - to the foreign country at current prices to obtain 3/40 TVS . So gain = 3/40 - /20 = 1/40 TUS by trading instead of producin TVS itself . Similarty, Foreign country trades Ya* = y's for / 45 cars , the gain is 1/45 - 1/95 = 225 Cars So - gain for home : 400 ( 1/40 ) = 10 , for foreign: 450 (275 ) = 4 2 QTV 30 20 30 10 QC 6 10 Home Foreign