Maths Olympiad Prep

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, 2023

Algebra Difficulty 2.0 Junior Prove it United Kingdom

The smallest four two-digit primes are written in different squares of a 2×22 \times 2 table. The sums of the numbers in each row and column are calculated. Two of these sums are 2424 and 2828. The other two sums are cc and dd, where c<dc < d. What is the value of 5c+7d5c + 7d?

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