What is i hcf of 21 and 28

\( 21|3 \\ 7 \ |7 \\ 1 \\\\ 21=3*7 \\\\ 28|2 \\ 14|2 \\ 7 \ |7 \\ 1 \\\\ 28=2^2*7 \\\\ H. C. F(21;28)\to\boxed{7} \)

The factors of 21 are 1, 3, 7, and 21.

The factors of 28 are 1, 2, 4, 7, 14, and 28.

The factors common to both numbers are 1 and 7.

The greatest one is ** 7**.

Ai făcut o greșeală. 84 is the Least Common Multiple (LCM), not the Highest Common Factor (HCF).

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