EC-CouncilCertified Encryption Specialist
Domain 3Objective 1
Number Theory and Mathematical Foundations ECES Practice Questions (Page 9)
Part of the Asymmetric Cryptography and Number Theory domain, which makes up ~17% of our current practice bank. EC-Council does not publish an official question count, but from its 120-minute exam (~50–80 total, ~9–14 in this domain), expect 3–5 from this objective — we provide 44 practice questions to prepare you well beyond it. (estimate)
44questions here
9free pages
11concepts
Questions 41–44
- 41
How many prime numbers are there between 20 and 30 (inclusive)?
Select an answer first - 42
A security engineer is analyzing an RSA implementation with modulus n = 77. To compute the private exponent, the engineer needs φ(77). What is φ(77)?
Select an answer first - 43
A developer is implementing a custom stream cipher that uses modular multiplication for key mixing. The cipher needs the multiplicative inverse of 7 modulo 60 to decrypt a message. What is the inverse, and does it exist?
Select an answer first - 44
An engineer is configuring an RSA-like system with modulus n = 100. To compute the private exponent, the engineer needs φ(100). What is φ(100)?
Select an answer first
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