5 pansies at $2.50 each is 5*2.50 = $<<5*2.5=12.50>>12.50
5 petunias at $1.00 each 5*1 = $<<5*1=5.00>>5.00
All total he spends 12.50+12.50+5.00 = $<<12.50+12.50+5.00=30.00>>30.00
The sale is 10% off so 30*.10 = $<<30*.10=3.00>>3.00
The purchase total now comes to 30-3 = $<<30-3=27.00>>27.00
He pays with a $50 bill so 50-27 = $<<50-27=23.00>>23.00
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