Answer: 8 hours
Step-by-step explanation:
Given : The cost "c" (in dollars) of renting a paddle board for "h" hours is given by \(c=25+7h\)
Now, put the value of c= 81 in the given equation, then we have
\(81=25+7h\)
Subtract 25 on both sides , we get
\(7h=81-25\\\\\Rightarrow\ 7h=56\)
Now, divide 7 on the both sides , we get
\(h=8\)
Hence, the number of hours for the cost of $81 = 8
