Given that Mariana wears her coat only when temperature is colder than - 4°C
Recall that lower temperature values indicate higher degree of coldness ;
Hence, Mariana will only wear her coat when temperature values are lesser than - 4°C ; this means that the temperature at that period is colder than - 4°C.
Hence, the inequality expression which is only true for temperatures when Mariana wears her coat can be written as :
