Boy Mow Chau's answer to Sg's Secondary 1 Maths Singapore question.
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answer is 7
Date Posted:
4 years ago
explanation ...
supposing a divided by n
gives quotient c and remainder r,
then a = c x n + r,
and if b divided by n
gives quotient d and remainder r
then b = d x n + r.
a - b = (c x n + r) - (d x n + r)
= c x n - d x n
= (c - d) x n
so (c - d) and n are factors of (a-b) .
supposing a divided by n
gives quotient c and remainder r,
then a = c x n + r,
and if b divided by n
gives quotient d and remainder r
then b = d x n + r.
a - b = (c x n + r) - (d x n + r)
= c x n - d x n
= (c - d) x n
so (c - d) and n are factors of (a-b) .
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