Dear student,
Initially,
number of rose plants=480
number of sunflower plants = 360
40 more sunflowers are added in the garden
finally,
number of rose plants=480
number of sunflower plants = 360+40=400
the new ratio of rose and sunflower plants in the garden
=
So, the new ratio of rose and sunflower plants in the garden is 6:5
Regards!