Finding the Fourth Proportional to 1,399.23, 2,098.56 and 425.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.23 : 2,098.56 = 425.10 : x
2. Step 2: Convert to fraction form
   1,399.23/2,098.56 = 425.10/x
3. Step 3: Cross multiply
   1,399.23x = 2,098.56 × 425.10
4. Step 4: Simplify right side
   1,399.23x = 892,097.86
5. Step 5: Solve for x
   x = 892,097.86/1,399.23
6. Step 6: Final answer
   x = 637.56