She wants to send a dozen carnations that cost $4/dz to each of her 5 teachers, so 4*5 = $<<4*5=20>>20
She has 14 friends and she knows a dozen carnations is cheaper than buying 12 single carnations. So 14-12 = <<14-12=2>>2 single carnations are needed
A single carnation cost $0.50 so 2*.50 = $<<2*.50=1.00>>1.00
All total she will spend 20+4+1 = $<<20+4+1=25.00>>25.00 on carnations
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