Finding the Fourth Proportional to 1,404.12, 2,105.46 and 429.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.12 : 2,105.46 = 429.96 : x
2. Step 2: Convert to fraction form
   1,404.12/2,105.46 = 429.96/x
3. Step 3: Cross multiply
   1,404.12x = 2,105.46 × 429.96
4. Step 4: Simplify right side
   1,404.12x = 905,263.58
5. Step 5: Solve for x
   x = 905,263.58/1,404.12
6. Step 6: Final answer
   x = 644.72