18 x Mentos $0.50 = $9.00
2 x Mentos Gum $1.00 = $2.00
I purchased these coupons on ebay, 20 for $3.50. Each coupon cost me $0.175
I used 11 coupons which doubled to $1.00. Making each item free.
11 x $0.175 = $1.925
$1.952 / 20 = $0.0965
So roughly $0.10 per mentos
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