Which of these congruences is NOT true?

38 \equiv 3 \pmod{7}

Correct answerYour answer

50 \equiv 2 \pmod{8}

Correct answerYour answer

29 \equiv 5 \pmod{6}

Correct answerYour answer

41 \equiv 6 \pmod{8}

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

$a \equiv b \pmod{n}$ exactly when $n$ divides $a - b$ .
$41 - 6 = 35$ , not a multiple of 8. The others give 35, 48 and 24, multiples of 7, 8 and 6.

Ten questions from Modulo Arithmetic & Congruence, at your own pace.

Ten questions from Modulo Arithmetic & Congruence, at your own pace.

Explanation