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Alien Currency

Age 14 to 16 Short
Challenge Level

On planet Zog, they use green and blue bank notes.

Three green notes and eight blue notes are worth 46 zogs.
Eight green notes and three blue notes are worth 31 zogs.

How many zogs are two green notes and three blue notes worth?


If you liked this problem, here is an NRICH task that challenges you to use similar mathematical ideas.


This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.