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SASMO 2015 P2 Q3  The sum of two numbers is 300. One number is 5 times of the other number. What is the difference between the two numbers? 
Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems
x = 1u  y = 5u  6u = 300  1u = 50  So, x=50, y=250  Difference 250-50=200 