Estimate the sum `5290 + 17986` by estimating the numbers to their nearest
(i) hundreds
(ii) thousands.

Options

A. (i)`23300`
(ii)`23000`
B. (i)`23900`
(ii)`25000`
C. (i)`23870`
(ii)`23900`
D. (i)`23700`
(ii)`26000`

Answer

To estimate the sum of 5290 and 17986 by rounding to the nearest hundreds and thousands, we can follow these steps:

### Step 1: Estimate to the Nearest Hundreds
1. **Round 5290 to the nearest hundred**:
- Look at the tens digit (9). Since it is 5 or more, we round up.
- Therefore, 5290 rounds to **5300**.

2. **Round 17986 to the nearest hundred**:
- Look at the tens digit (8). Since it is 5 or more, we round up.
- Therefore, 17986 rounds to **18000**.

3. **Add the estimated values**:
- Now, we add the rounded numbers:
- 5300 + 18000 = **23300**.

### Step 2: Estimate to the Nearest Thousands
1. **Round 5290 to the nearest thousand**:
- Look at the hundreds digit (2). Since it is less than 5, we round down.
- Therefore, 5290 rounds to **5000**.

2. **Round 17986 to the nearest thousand**:
- Look at the hundreds digit (9). Since it is 5 or more, we round up.
- Therefore, 17986 rounds to **18000**.

3. **Add the estimated values**:
- Now, we add the rounded numbers:
- 5000 + 18000 = **23000**.

### Final Answers:
- The estimated sum to the nearest hundreds is **23300**.
- The estimated sum to the nearest thousands is **23000**.

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