To make it more clearer, just make use of the formula below:T = 200 + 10* ((English-70)/10.43+(Maths-64)/12.93+(Science-66)/12.33+(Chinese-73)/9.43)According to above formula, The highest achieveable T-score for chinese is 50 + 10*(Chinese-73)/9.43 = 50+ 10*(100-73)/9.43 = 78.6If we make chinese test much easy, increase its average score to 78, then the highest achieveable T-score for chinese will be 50+10*(100-78)/9.43= 73.3, down 5 points, if the other subjects’ highest achieveable T-score maintain around 78, then the weightage of chinese actually decrease.In order to compare different MT, to be fair we need bring in one more factor to normalize the difference. For example we use Malay as a reference.Then the T-score for chinese student should translate to the following formula:50 + (highest achieveable Malay T-score/highest achieveable Chinese T-score)10(Chinese-73)/9.43. Only by doing so, different MT can compare at same level