Since Tapiwa raked 5% more leaves than Adam did. She raked the amoutn that Adam raked PLUS 5% of what he raked, so she raked 105% of what he raked. Since Tapiwa raked 357 liters of leaves, set up the equation:
357 = 1.05x
Divide by 1.05.
340 = x
Adam raked 340 liters of leaves.
Hope this helps