They bought 12 pineapples for $1.25 apiece so 12*1.25 = $<<12*1.25=15.00>>15.00
The pineapples cost $15.00 and it will cost $21.00 to ship so all total, it costs 15+21 = $<<15+21=36.00>>36.00
In total it costs $36.00 to ship home a dozen pineapples so each pineapple costs 36/12 = $<<36/12=3.00>>3.00 apiece
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