Make 24 - Four Cards

Simple puzzle game. Can you make 24 by combining 4 cards using arithmetic operators?
P.S. It is impossible (sometimes)

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Test your mental speed! The rules are simple. Perform arithmetic operations using all four cards to equate 24. Simply drag a card on top of another and select an operation.

This game exercises your numerical and pattern-matching skills. It is also a great way for children to practice their math fundamentals.