Knives 2, 3 & 4 will cost $4.00 each to sharpen so that’s 3*4 = $12.00
Knives 5-9 will cost $3.00 each to sharpen so that’s 5*3 = $<<5*3=15.00>>15.00
The first knife will cost $5.00, the next 3 cost $12.00 and the rest cost $15.00 for a total of 5+12+15 = $<<5+12+15=32.00>>32.00
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