Let 5x = Daniel's share
7x = Elliot's share
8x = Frank's share
8x = 5x + 2781
3x = 2781
x = 927
Daniel's share = 5x = $4635
Elliot's share = 7x = $6489
Frank's share = 8x = $7416
Amount shared = 4635 + 6489 + 7416 = $18540