Number Puzzle 431
1. **Problem Statement:** Use the numbers 25, 8, 100, 2, 75, and 50 exactly once each with any operations to reach the target value 431.
2. **Understanding the Rules:**
- Each number must be used exactly once.
- Operations (+, -, *, /) can be used multiple times.
- The goal is to combine these numbers to get exactly 431.
3. **Approach:**
- Start by considering combinations of numbers that sum or multiply close to 431.
- Use addition and subtraction to adjust the total.
4. **Example Solution:**
- Calculate $$100 \times 4 = 400$$ (using 100 and 2 twice is not allowed, so instead use 100 and 2 to get 200, then multiply by 2 again is invalid, so try another way)
- Instead, try $$75 + 50 = 125$$
- Then $$125 \times 2 = 250$$
- Add 100: $$250 + 100 = 350$$
- Add 25: $$350 + 25 = 375$$
- Add 8: $$375 + 8 = 383$$
- We need 431, so try multiplying 8 by something else or rearranging.
5. **Correct Calculation:**
- Multiply 8 and 50: $$8 \times 50 = 400$$
- Add 75: $$400 + 75 = 475$$
- Subtract 25: $$475 - 25 = 450$$
- Subtract 100: $$450 - 100 = 350$$
- Add 2: $$350 + 2 = 352$$ (Not 431, so try another way)
6. **Final Working Solution:**
- Multiply 8 and 50: $$8 \times 50 = 400$$
- Add 75: $$400 + 75 = 475$$
- Subtract 25: $$475 - 25 = 450$$
- Subtract 100: $$450 - 100 = 350$$
- Add 2: $$350 + 2 = 352$$ (Still not 431, so try another approach)
7. **Alternative Solution:**
- Multiply 75 and 2: $$75 \times 2 = 150$$
- Add 100: $$150 + 100 = 250$$
- Multiply 8 and 25: $$8 \times 25 = 200$$
- Add 250 and 200: $$250 + 200 = 450$$
- Subtract 50: $$450 - 50 = 400$$ (Still not 431)
8. **Try using division:**
- Divide 100 by 2: $$100 \div 2 = 50$$
- Add 50: $$50 + 50 = 100$$
- Multiply 8 and 25: $$8 \times 25 = 200$$
- Add 100 and 200: $$100 + 200 = 300$$
- Add 75: $$300 + 75 = 375$$
- Add 50: $$375 + 50 = 425$$ (Close to 431)
9. **Adjusting to 431:**
- Instead of adding 50, add 8: $$375 + 8 = 383$$
- Need 48 more, try multiplying 2 and 25: $$2 \times 25 = 50$$
- Add 50 to 383: $$383 + 50 = 433$$ (Too high)
10. **Conclusion:**
- The problem requires creative use of operations and numbers.
- The key is to try different combinations and operations to reach exactly 431.
**Final note:** This problem is a challenging puzzle that encourages practice with arithmetic operations and number manipulation.