Divisible By 4
1. **Problem Statement:** Determine which numbers from the list 38, 45, 76, 92, 288, 358, 876, 1580, 23, 494 are divisible by 4.
2. **Rule for divisibility by 4:** A number is divisible by 4 if the number formed by its last two digits is divisible by 4.
3. **Check each number:**
- 38: last two digits 38; 38 ÷ 4 = 9.5 (not divisible)
- 45: last two digits 45; 45 ÷ 4 = 11.25 (not divisible)
- 76: last two digits 76; 76 ÷ 4 = 19 (divisible)
- 92: last two digits 92; 92 ÷ 4 = 23 (divisible)
- 288: last two digits 88; 88 ÷ 4 = 22 (divisible)
- 358: last two digits 58; 58 ÷ 4 = 14.5 (not divisible)
- 876: last two digits 76; 76 ÷ 4 = 19 (divisible)
- 1580: last two digits 80; 80 ÷ 4 = 20 (divisible)
- 23: last two digits 23; 23 ÷ 4 = 5.75 (not divisible)
- 494: last two digits 94; 94 ÷ 4 = 23.5 (not divisible)
4. **Numbers divisible by 4:** 76, 92, 288, 876, 1580
5. **Answer for 6a:** Circle 76, 92, 288, 876, 1580.
6. **Problem 6b:** Is it correct to say a number is divisible by 4 if half of the number is even?
7. **Explanation:**
- If half of a number is even, it means that when you divide the number by 2, the result is an even number.
- An even number can be written as $2k$ for some integer $k$.
- So, if half the number is even, the number can be written as $2 \times (2k) = 4k$.
- This means the original number is a multiple of 4 and thus divisible by 4.
8. **Conclusion:** Yes, it is correct to say a number is divisible by 4 if half of the number is even because that implies the number is a multiple of 4.