At Mrs. Dawson's rose garden, there are 10 rows of roses. In each row, there are 20 roses where 1/2 of these roses are red, 3/5 of the remaining are white and the rest are pink. How many roses at Mrs. Dawson's rose garden are pink?
There are 20 x 1/2 = 10 red roses in each row.
So there are 20 - 10 = 10 roses that are not red in each row.
Out of the 10 remaining roses in each row, 10 x 3/5 = 6 roses are white.
Thus, there are 10 - 6 = 4 pink roses in each row.
Therefore, Mrs. Dawson has 4 pink roses each in 10 rows for a total of 4 x 10 = 40 pink roses in her rose garden.