Color Management

You need to use complete color management workflow to ensure that colors are as close as possible.
RGB colorspace (as used by monitors and inkjet printers) are device dependent which means same RGB values almost always look different on different output device.
It's very complicated if you don't know too much about color management. Average quality hardware alone (colorimeter, spectrophotometer) may cost near $1000 to get good results although you can always get lucky to get things right with spending extra money.