A sheet has 16 cookies, so if each church member baked 10 sheets, they each baked 10 sheets/person * 16 cookies/sheet = <<10*16=160>>160 cookies/person
The total number of church members who decided to volunteer is 100, so in total, they baked 160 cookies/person * 100 people = <<100*160=16000>>16000 cookies
#### 16000