Math help please?

A TV station executive is planning the new lineup for next season's shows. On Monday nights, there will be 3 sitcoms and 4 dramas, for a total of 261 minutes of programming, not counting commercials. On Tuesday nights, he has scheduled 2 sitcoms and 4 dramas, for a total of 238 minutes of non-commercial programming. All sitcoms have the same length and all dramas have the same length. How long is each type of show?