Answer:
28
Step-by-step explanation:
Given: In order to vote on any decision, a club requires the presence of
of all club members. to be approved, a proposal needs
of the votes cast. a club has membership of
.
To Find: minimum number of votes needed for a proposal to be approved.
Solution:
Total number of members in club 
Minimum presence required for vote on any decision 
Minimum presence required for vote 

Minimum vote required to approve a proposal 
Total vote cast 
putting value,
Minimum vote required to approve a proposal

Hence minimum 28 votes are required for a proposal to be approved.