How many pounds are in nine liters

I realize that the conversions aren't compatible, so here is the situation:

I am trying to buy some soil that is being sold by the liter. There are nine liter bags available. I need about twenty pounds. How many bags would that come out to?

Thank you for your assistance!

Soil has a density of about 105 lbs/ft³ and there are about 0.0353 cubic feet in a liter. So we have
9*.0353 = .3177 ft³

which means w ehave about
105 * .3177 = 33.36 lbs

So you need less than a whole bag, specifically 20/33.36 ≈ .6. So .6 of a bag would do, or 5.4 liters.

Good luck!