Finding the Fourth Proportional to 1,123.54, 1,684.53 and 429.37

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.54 : 1,684.53 = 429.37 : x
2. Step 2: Convert to fraction form
   1,123.54/1,684.53 = 429.37/x
3. Step 3: Cross multiply
   1,123.54x = 1,684.53 × 429.37
4. Step 4: Simplify right side
   1,123.54x = 723,282.43
5. Step 5: Solve for x
   x = 723,282.43/1,123.54
6. Step 6: Final answer
   x = 643.75