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UKMT Grey Kangaroo, 2022

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Mowgli asked a snake and a tiger what day it was. The snake always lies on Monday, Tuesday and Wednesday but tells the truth otherwise. The tiger always lies on Thursday, Friday and Saturday but tells the truth otherwise. The snake said "Yesterday was one of my lying days". The tiger also said "Yesterday was one of my lying days". What day of the week was it?

(A) Thursday (B) Friday (C) Saturday (D) Sunday (E) Monday

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