Question 1033043
You need to find the cost of 1 cookie
There are {{{ 10 }}} cookies in each packet
So, there are {{{ 9*10 = 90 }}} cookies in 
{{{ 9 }}} packets
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Now you can find:
[ total cost ] / [ total number of cookies ]
{{{ 15.9 / 90 = .177 }}}
The cost of each cookie is 17.7 cents
Hope this helps