The 10%

I found a 10% discount brochure for Pepper Lunch this afternoon, and I told my friend, " Hey, if we get a salmon rice, which is $10 and we'll get one dollar discount with the brochure. And if we get a $9 curry rice, we only got $0.90 of discount. So, it's more worthwhile to get a salmon rice, since we only have to pay $9 but for curry rice, we still have to pay $9.10....... Hmm.... I'll get a salmon rice then...."
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