Hanna can buy $300/$2 = <<300/2=150>>150 roses.
So, Jenna will receive 1/3 x 150 = <<1/3*150=50>>50 roses.
While Imma will receive 1/2 x 150 = <<1/2*150=75>>75 roses.
Therefore, Hanna gives a total of 50 + 75 = <<50+75=125>>125 roses to her friends.
#### 125