That's strange wording Galina, but I would say that it means this:

"What fractional part" = "f"

"of 8" means "times 8"

"is" means "="

"eight hundreths" = "8 / 100"

So f x 8 = 8 / 100.

If we divide by 8 on both sides of this equation, the 8 on the left side is cancelled. Also, the eight on the right side is cancelled.

So f = 1 / 100.

Thus, the answer is one hundredth.

Cheers,
Stephen La Rocque.