Flower prices (per unit):
Roses: $5
Carnations: $3
The bouquet is made of 15 flowers (roses and carnations). If we have R roses and C carnations, then:
R + C = 15 ...(1)
The total price is $61, so:
5R + 3C = 61 ...(2)
So we have 2 equations and 2 unknowns, so the system of equation is solvable. From equation (1):
C = 15 - R
Replacing this on (2):
5R + 3(15 - R) = 61
Solving for R:
5R + 45 - 3R = 61
2R = 61 - 45
2R = 16
R = 8
So there are 8 roses in the bouquet. To have 15 flowers, there need to be 7 carnations.
Answer:
8 roses
7 carnations