Eric Nicholas K's answer to glittr's Secondary 4 E Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
1st
If we are certain that Kate only stays in the second floor, then there are now only 15 possibilities altogether as compared to the old 30 possibilities, as detailed in the new table.
glittr
Glittr
5 years ago
thanks for the effort ! is there a non-diagram method ?