Step-by-step explanation: Step-by-step explanation: The sister has to pay rent which is $60 which means she has negative $30 in three days the sister would have earned $60 and in 3 days the brother would have earned $60
Population are always modeled by exponential growth equation given by: f(x)=a(1+b)^t where: a=original number b=rate of growth t=time thus f(x)=412(1.05)^t the population after 9 months will be: f(9)=412(1.05)^9=639.15=639
