Question 136072
P=42+20ln(11t+1)
so

180=42+20ln(11t+1)
then
138=20ln(11t+1)
ln(11t+1)=138/20=6,9
then

exp(ln(11t+1))=exp(6,9)

11t+1=992,2747
11t=991,2747
t=90,1