Example 1: Round $42,\!850,\!671$ to the nearest million

1. The million digit is 2 (in 42,850,671).
2. The next digit is 8 (greater than 5), so we increase 2 to 3.
3. Replace digits to the right with zeros:

$42,\!850,\!671 \approx 43,\!000,\!000$

Example 2: Round $42,\!850,\!671$ to the nearest ten million

1. The ten million digit is 4.
2. The next digit is 2 (less than 5), so 4 stays the same.
3. Replace digits to the right with zeros:

$42,\!850,\!671 \approx 40,\!000,\!000$

Example 3: Round $678,\!912$ to the nearest thousand

1. The thousand digit is 8.
2. The next digit is 9 (greater than 5), so increase 8 to 9.
3. Replace right digits with zeros:

$678,\!912 \approx 679,\!000$

Example 4: Round $34,\!649$ to the nearest hundred

1. The hundred digit is 6.
2. The next digit is 4 (less than 5), so keep 6 the same.
3. Replace digits to the right with zeros:

$34,\!649 \approx 34,\!600$

Example 5: Round $3,\!999$ to the nearest thousand

1. The thousand digit is 3.
2. The next digit is 9 (≥5), so 3 becomes 4.
3. Replace all right digits with zeros:

$3,\!999 \approx 4,\!000$

Example 6: Round $78,\!542$ to the nearest ten thousand

1. The ten thousand digit is 7.
2. The next digit is 8 (≥5), so increase 7 to 8.
3. Replace remaining digits with zeros:

$78,\!542 \approx 80,\!000$

Steps:

1. Stand at the digit of the required decimal place.
2. Look at the digit to the right of it.
3. If it is 5 or more, round up (increase the digit by 1).
4. If it is less than 5, do not change the digit.
5. Replace all digits to the right with zeros (or drop them if not needed).

Example 1: Round $0.24736$ to 1 decimal place

1. Look at the first decimal: 2
2. The next digit is 4 (less than 5), so keep 2
3. Answer: $0.24736 \approx 0.2$

Example 2: Round $0.24736$ to 2 decimal places

1. Look at second decimal: 4
2. The next digit is 7 (≥5), so increase 4 to 5
3. Answer: $0.24736 \approx 0.25$

Example 3: Round $0.24736$ to 3 decimal places

1. Look at third decimal: 7
2. The next digit is 3 (less than 5), so keep 7
3. Answer: $0.24736 \approx 0.247$

Example 4: Round $8.7659$ to 2 decimal places

1. Second decimal is 6, next is 5 (≥5), so 6 becomes 7
2. Answer: $8.7659 \approx 8.77$

Example 5: Round $3.14159$ to 3 decimal places

1. Third decimal is 1, next is 5 (≥5), so 1 becomes 2
2. Answer: $3.14159 \approx 3.142$

Example 6: Round $5.9999$ to 2 decimal places

1. Second decimal is 9, next is 9 (≥5), increase 9 to 10 → carry over
2. $5.9999 \approx 6.00$