Finding the Fourth Proportional to 1,123.24, 1,685.61 and 430.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.24 : 1,685.61 = 430.49 : x
2. Step 2: Convert to fraction form
   1,123.24/1,685.61 = 430.49/x
3. Step 3: Cross multiply
   1,123.24x = 1,685.61 × 430.49
4. Step 4: Simplify right side
   1,123.24x = 725,638.25
5. Step 5: Solve for x
   x = 725,638.25/1,123.24
6. Step 6: Final answer
   x = 646.02