Emily writes down the largest two-digit prime such that each of its digits is prime. Krish writes down the smallest two-digit prime such that each of its digits is prime. Kirsten subtracts Krish’s number from Emily’s number. What answer does Kirsten obtain?
Select one option, then click Submit.
14
20
36
45
50
Select an option, then submit.
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Junior Mathematical Challenge (2019)
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