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Estonia algebra
Problem
Does there exist a positive integer whose
a. digit sum is 100 more than the product of digits?
b. product of digits is 100 more than the digit sum?
c. product of digits is 100 times greater than the digit sum?
a. digit sum is 100 more than the product of digits?
b. product of digits is 100 more than the digit sum?
c. product of digits is 100 times greater than the digit sum?
Solution
Answer: (a) Yes; (b) Yes; (c) Yes.
(a) The number , consisting of ones, works. Its product of digits is and digit sum .
(b) The number works. Its product of digits is and digit sum .
(c) The number has product of digits and digit sum .
(a) The number , consisting of ones, works. Its product of digits is and digit sum .
(b) The number works. Its product of digits is and digit sum .
(c) The number has product of digits and digit sum .
Final answer
(a) Yes; (b) Yes; (c) Yes
Techniques
Integers