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Postage

Stage: 4 Challenge Level: Challenge Level:1

image of stampThe country Sixtania prints postage stamps with only three values 6 lucres, 10 lucres and 15 lucres (where the currency is in lucres).

Which values cannot be made up with combinations of these postage stamps? Prove that all other values can be made up.

The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities can be found here.
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