Question 1187981: A cut-tail prime is a prime number that keeps giving prime numbers as its last digit is continually removed. For example, 37397 is a cut-tail prime because 37397 and 3739 and 373 and 37 and 3 are all primes. The number of three-digit cut-tail primes is
A)12 B)13 C)14 D)15 E)16
Found 3 solutions by ikleyn, MarkSingh-, Alan3354:
Answer by ikleyn(52784)   (Show Source):
You can put this solution on YOUR website! .
14. ANSWER
See this Wikipedia article
https://en.wikipedia.org/wiki/Truncatable_prime
where ALL 83 EXISTING right-truncatable primes are listed.
Of them, there are exactly 14 three-digit numbers.
// Kind of useless knowledge which gives NOTHING and teaches NOTHING.
Answer by MarkSingh-(4)  (Show Source):
You can put this solution on YOUR website! Three-digit cut-tail primes:
233, 239, 293, 311, 313, 317, 373, 379, 593, 599, 719, 733, 739, 797 = 14
numbers
Answer by Alan3354(69443)  (Show Source):
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