Answer:
Angelica's bouquet has 7/12 pink roses.
Explanation:
A dozen is defined to be a set of 12 in number or group pf anything. Here, in this case we have roses so a dozen of roses means '12 roses'.
5 of the roses in the bouquet are white roses, so the fraction of white roses will be 5 divided by the total number of roses i.e. 12:
White roses =

Rest of the roses are pink, so we can simply subtract 5 from 12 to get the number of roses which will be 12 - 5 = 7
Or
we can subtract the fraction of white roses from 1 to get the fraction of pink roses in the bouquet:
Pink roses =
=
