Hmm..I'll try..but seeing that 95% get it wrong, who knows if this is correct...
r= roses
s= sunflowers
p= purple flowers
So:
r+r+r=60: 3r=60 (I won't say that r=20...yet, as this is meant to be hard...)
r+2p=30
p-2s=3
s+r*p=?
ok, so using the information that we have, we can say that it is best to turn s+r*p into all p's. So:
r=30-2p
s=(3-p)/2
So, the last question wants:
(3-p)/2+30p-2p^2, which is:
(3-p+60)/2-2p^2
Based on what we know, p should be 10. So, plugging that in, we get:
53/2-200.
I really don't want to simply that, but you get the idea, it's different from what 'normal' people would have got...unless...I made a mistake along the way, which is probably what happened...
:)