if it was longer maybe it would be different but for 5 days a healthy person can eat nothing at all and be just fine, some people do this voluntarily as an occasional fasting. so that being said, of course give the pregnant lady anything she needs because the baby could be seriously affected if she doesn't eat enough. give the injured person anything they need so they don't die. that leaves 2 fit adults and an adolescent. I'm not sure if "rationned normally" means that the woman and injured guy get what they fully need but lets say it does. lets say they eat 3 meals a day but two get big meals. that means in total there is 18 large meals and 27 regular meals. lets say the pregnant woman is in her second trimester and needs 20% more resources and the same for injured guy. they both need an extra 6 big meals so about 15 regular meals for the both of them. that leaves 12 meals to be split in 3 so the 3 other people would get one regualr meal a day except for the last day where they get nothing.