Context :

Aims : We present the results of our analysis of KIC 4150611 ( HD 181469 ) – an interesting , bright quintuple system that includes a hybrid \delta Sct/ \gamma Dor pulsator .
Four periods of eclipses – 94.2 , 8.65 , 1.52 and 1.43 d – have been observed by the Kepler satellite , and three point sources ( A , B , and C ) are seen in high angular resolution images .

Methods : From spectroscopic observations made with the HIDES spectrograph attached to the 1.88-m telescope of the Okayama Astrophysical Observatory ( OAO ) , for the first time we calculated radial velocities ( RVs ) of the component B – a pair of G-type stars – and combined them with Kepler photometry in order to obtain absolute physical parameters of this pair .
We also managed to directly measure RVs of the pulsator , also for the first time .
Additionally , we modelled the light curves of the 1.52 and 1.43-day pairs , and measured their eclipse timing variations ( ETVs ) .
We also performed relative astrometry and photometry of three sources seen on the images taken with the NIRC2 camera of the Keck II telescope .
Finally , we compared our results with theoretical isochrones .

Results : The brightest component Aa is the hybrid pulsator , transited every 94.2 days by a pair of K/M-type stars ( Ab1+Ab2 ) , which themselves form a 1.52-day eclipsing binary .
The components Ba and Bb are late G-type stars , forming another eclipsing pair with a 8.65 day period .
Their masses and radii are M _ { Ba } = 0.894 \pm 0.010 M _ { \odot } , R _ { Ba } = 0.802 \pm 0.044 R _ { \odot } for the primary , and M _ { Bb } = 0.888 \pm 0.010 M _ { \odot } , R _ { Bb } = 0.856 \pm 0.038 R _ { \odot } for the secondary .
The remaining period of 1.43 days is possibly related to a faint third star C , which itself is most likely a background object .
The system ’ s properties are well-represented by a 35 Myr isochrone , basing on which the masses of the pulsator and the 1.52-day pair are M _ { Aa } = 1.64 ( 6 ) M _ { \odot } , and M _ { Ab,tot } = 0.90 ( 13 ) M _ { \odot } , respectively .
There are also hints of additional bodies in the system .

Conclusions :