7 There are 10 boys and 20 girls in a class. The class has a test. The mean mark for all the class is 60 The mean mark for the girls is 54 Work out the mean mark for the boys
Please show working out!
totalall=(nboys+ngirls)mtotal=(10+20)60=1800totalgirls=ngirlsmgirls=20×54=1080totalboys=totalall−totalgirls=1800−1080=720mboys=totalboysnboys=72010=72
kind of a sexist problem :P
Thanks for the answer!