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MathNet 2022-part-04 — 197 problems (EN–VI) Question 57

Math Olympiad Vault · MathNet 2022-part-04 — 197 problems (EN–VI)

Question 57

Call a whole number ordinary if the product of its digits is less than or equal to the sum of its digits. How many numbers from the set $\{1,2, \ldots, 999\}$ are ordinary?
(a) 151
(b) 162
(c) 230
(d) 241