~only answer if you know for sure~
(state which answer goes to which question ) : )

After 8 days, he has spent . Half his starting money would be . Hence, he has spent less than half his starting money.

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If A and B are in a ration a:b then for each a of A there are b of B.

Hence for each 4 soccer players there is 1 volleyball player.
The number of soccer players is 4 times the number of volleyball players (the top left answer is correct).
If there are 4 volleyball players, there are thus 4*4=16 soccer players (and not 12)

If there are 16 soccer players, there are then 16/4=4 volleyball players, thus a total of 20 players: the third answer (bottom left) is wrong

Whose mistake? can you give more details to what the question is asking?