Lily spends $5+$8=$<<5+8=13>>13 on celery and bread.
Lily spends $12*(50/100)=$<<12*(50/100)=6>>6 on cereal.
Lily gets 10% off the milk, so she pays 100% - 10% = 90% of its original price.
Lily spends $10*90%=$<<10*90*.01=9>>9 on milk.
She spends $1*6=$<<1*6=6>>6 on potatoes.
Thus, she has $60-$13-$6-$9-$6=$<<60-13-6-9-6=26>>26 left over for coffee.
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