Only 1/2 Of 1 Of All Collisions Involve

Which is grammatically correct? I can only do so much in this time. or I can do only so much in this time.

only 1/2 of 1 of all collisions involve 1

Only does not carry a vague implication of a small number. It carries a connotation of a small number, sometimes one alone; an only child, the only redhead, the one and only. Only: "being the single one or the relatively few of the kind; having no sibling or no sibling of the same sex; single in superiority or distinction; unique; the best."

only 1/2 of 1 of all collisions involve 2

phrase meaning - Does "one of the only" actually mean anything ...

only 1/2 of 1 of all collisions involve 3

WUSA: Nearly 1/4 of near-midair collisions involve military aircraft, CBS report finds

only 1/2 of 1 of all collisions involve 4

WASHINGTON — A couple of thousand near mid-air collisions involve military aircraft, according to a new report by CBS News. Their team analyzed more than 8,000 near misses voluntarily reported to the ...

only 1/2 of 1 of all collisions involve 5