Aflorist wishes to make bouquets of mixed spring flowers. part of each bouquet is to be tulips at $5 a bunch and part is to be daffodils at $2 a bunch. how many bunches of each should she use to make 15 bouquets which she can sell for $3 a bouquet.

To solve the problem we are going to take into account a system of equations:
 Let:
 x = number of tulips
 y = amount of daffodils
 We have then:
 x + y = 15
 5x + 2y = 45
 Resolving we have:
 Step 1:
 Multiply equation 1 by 2
 2x + 2y = 30
 5x + 2y = 45
 Step 2: 
 subtract equation two from one:
 3x = 15
 x = 15/3 = 5
 Step 3: 
 Clear y:
 x + y = 15
 y = 15-x
 y = 15-5
 y = 10
 
 she should use 5 tulips and 10 daffodils

$11,000 is the answer you are looking for