Question 473653
A lot of this information can be ignored, unless you're a journalist. (smile)
How much money do they have to spend o trees and shrubs?
4200 - 2400 - 1500 = 300
How many trees and shrubs did they plant?  33
t = number of trees
s = number of shrubs
How many trees?  t
How many shrubs?  33-t
That's a key thing to substitute.
Trees are $32; shrubs are $4.
Since the spent $300, we can say:
32*t + (33-t)*4 = 300
Simplify
32t + 132 - 4t = 300
28t = 168
t = 168/28
t = 6
.
That means they planted 33-6 = 27 shrubs.
.
To check, how much do 27 shrubs cost?
27*4 = $108
How much did they spend on 6 trees?
6*32 = $192
How much in total?
108 + 192 = 300
That's correct!
.
Answer:
They purchased and planted 6 trees and 27 shrubs.
.
Done.