Question 20
What is the greatest 2-digit number that can be written as a sum of two different prime numbers in exactly two different ways?
Interpretation: The order of the two primes is ignored; the two primes in each sum must be unequal.
Answer format: enter the integer answer without units. Leading zeros are optional; the original paper uses four-digit boxes.
Interpretation: The order of the two primes is ignored; the two primes in each sum must be unequal.
Answer format: enter the integer answer without units. Leading zeros are optional; the original paper uses four-digit boxes.