How many three-digit numbers can be formed using only the digits 1, 2, 3, 4 and 5, if a digit may be repeated?

15Correct answerYour answer60Correct answerYour answer125Correct answerYour answer243Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

Each of the three places can be filled by any of the 5 digits, because repetition is allowed.
Numbers $= 5 \times 5 \times 5 = 125$ .

Worth noting

60 is $5 \times 4 \times 3$ , the count when digits may NOT repeat. 243 is $3^5$ , the powers the wrong way round.

Ten questions from Counting and Basic Probability, at your own pace.

Ten questions from Counting and Basic Probability, at your own pace.

Explanation