Ratios and Rates · Challenge problem

At 2 pm, a girl who is $1.5$ m tall casts a shadow $2$ m long, and a flagpole casts a shadow $12$ m long. At 5 pm, the girl's shadow is $3$ m long. How many meters long is the flagpole's shadow at 5 pm? (At any one moment, every shadow is the same number of times as long as the object's height.)