Question 12
Complete the table by dividing the decimals:
We move the decimal point to the left when dividing by powers of 10.
Step 1 — Understanding the rule
When we divide a decimal by 10, we move the decimal point one place to the left. When we divide by 100, we move the decimal point two places to the left. For 1000, we move three places. For 10000, we move four places.
Step 2 — Completing the second row
The original decimal is 21.1. We divide 21.1 by 10.
We divide 21.1 by 100.
We divide 21.1 by 1000.
We divide 21.1 by 10000.
Step 3 — Completing the third row
The original decimal is 0.13. We divide 0.13 by 10.
We divide 0.13 by 100.
We divide 0.13 by 1000.
We divide 0.13 by 10000.
Step 4 — Completing the fourth row
We are given that a decimal divided by 100 is 2.146. To find the original decimal, we multiply 2.146 by 100. When we multiply by 100, we move the decimal point two places to the right. So, the original decimal is 214.6.
Now we divide 214.6 by 10.
We divide 214.6 by 1000.
We divide 214.6 by 10000.
Step 5 — Completing the fifth row
We are given that a decimal divided by 10000 is 0.0058. To find the original decimal, we multiply 0.0058 by 10000. When we multiply by 10000, we move the decimal point four places to the right. So, the original decimal is 58.
Now we divide 58 by 10.
We divide 58 by 100.
We divide 58 by 1000.
Answer
The completed table is:
| Decimal | ÷ 10 | ÷ 100 | ÷ 1000 | ÷ 10000 | | :------ | :--- | :---- | :----- | :------ | | 18.7 | 1.87 | 0.187 | 0.0187 | 0.00187 | | 21.1 | 2.11 | 0.211 | 0.0211 | 0.00211 | | 0.13 | 0.013 | 0.0013 | 0.00013 | 0.000013 | | 214.6 | 21.46 | 2.146 | 0.2146 | 0.02146 | | 58 | 5.8 | 0.58 | 0.058 | 0.0058 |
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