To find the HCF of 306 and 657, we'll use the Euclidean algorithm:
Step 1: Apply division algorithm to 657 and 306
\( 657 = 306 \times 2 + 45 \)
Step 2: Now apply division algorithm to 306 and 45
\( 306 = 45 \times 6 + 36 \)
Step 3: Apply division algorithm to 45 and 36
\( 45 = 36 \times 1 + 9 \)
Step 4: Apply division algorithm to 36 and 9
\( 36 = 9 \times 4 + 0 \)
Since the remainder is now 0, the HCF is the last non-zero remainder.
Conclusion
The HCF of 306 and 657 is (3) 9.