= Solution
Give each permanent member weight seven, each nonpermanent member weight one, and use the strict threshold $t=38$. If a <coalition> omits a permanent member, its weight is at most $4\cdot7+10=38$, so it loses. If it includes all five permanent members and $r$ others, its weight is $35+r$, which exceeds 38 exactly when $r\ge4$. These are precisely the required winning <coalitions>. Thus a <weighted voting game> representation is
$$
\boxed{w_i=7\text{ for permanent members},\quad w_i=1\text{ otherwise},\quad t=38.}
$$
The strict-threshold convention is important: in the alternative convention requiring weight at least the quota, the quota is 39.
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