Rewrite the given numbers after inserting commas at appropriate places as
indicated. Also, names the different periods that are separated by the commas:
International system
(i) 391672 (ii) 5418458 (iii) 294751854

Answer

To rewrite the given numbers in the International system and insert commas at appropriate places, we will follow these steps:

### Step-by-Step Solution:

**(i) 391672**
1. Start from the rightmost digit and group the digits into sets of three, moving left.
2. The number is: 391,672.
3. The periods are:
- 391 (thousands)
- 672 (units)

**Final Representation:** 391,672 → Three hundred ninety-one thousand six hundred seventy-two.

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**(ii) 5418458**
1. Start from the rightmost digit and group the digits into sets of three, moving left.
2. The number is: 5,418,458.
3. The periods are:
- 5 (millions)
- 418 (thousands)
- 458 (units)

**Final Representation:** 5,418,458 → Five million four hundred eighteen thousand four hundred fifty-eight.

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**(iii) 294751854**
1. Start from the rightmost digit and group the digits into sets of three, moving left.
2. The number is: 294,751,854.
3. The periods are:
- 294 (millions)
- 751 (thousands)
- 854 (units)

**Final Representation:** 294,751,854 → Two hundred ninety-four million seven hundred fifty-one thousand eight hundred fifty-four.

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### Summary of Answers:
1. **391672** → 391,672 → Three hundred ninety-one thousand six hundred seventy-two.
2. **5418458** → 5,418,458 → Five million four hundred eighteen thousand four hundred fifty-eight.
3. **294751854** → 294,751,854 → Two hundred ninety-four million seven hundred fifty-one thousand eight hundred fifty-four.

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