Medium
In a certain code, 123 means 'It is green', 345 means 'Dog is jumping', 356 means 'Is jumping good', 728 means 'Green pet parrot', and 637 means 'Parrot is good'. What is the code for 'Is'?
Explanation
Explanation
Comparing 'Dog is jumping' (345) and 'Is jumping good' (356), the digit common to both codes representing a common word needs further comparison; cross-checking with 'Parrot is good' (637) and 'It is green' (123), the digit 3 consistently appears wherever 'is' appears, so 3 codes for 'Is'.
PRO TIP
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