Finding the Fourth Proportional to 1,404.40, 2,106.52 and 430.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.40 : 2,106.52 = 430.50 : x
2. Step 2: Convert to fraction form
   1,404.40/2,106.52 = 430.50/x
3. Step 3: Cross multiply
   1,404.40x = 2,106.52 × 430.50
4. Step 4: Simplify right side
   1,404.40x = 906,855.78
5. Step 5: Solve for x
   x = 906,855.78/1,404.40
6. Step 6: Final answer
   x = 645.73