The squares of which of the following would be odd numbers?
(i) 431                 (ii) 2826                 (iii) 7779              (iv) 82004

Explanation

To determine which of the given numbers have odd squares, we need to check the unit digit of each number. The unit digit will help us identify whether the square of the number is odd or even. An odd number has a unit digit of 1, 3, 5, 7, or 9, while an even number has a unit digit of 0, 2, 4, 6, or 8.

Let's analyze each number step by step:

### Step 1: Check the first number, 431
- The unit digit of 431 is **1**.
- The square of 1 is **1** (which is odd).
- Therefore, the square of 431 is odd.
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