Finding the Fourth Proportional to 1,123.49, 1,685.32 and 343.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.49 : 1,685.32 = 343.56 : x
2. Step 2: Convert to fraction form
   1,123.49/1,685.32 = 343.56/x
3. Step 3: Cross multiply
   1,123.49x = 1,685.32 × 343.56
4. Step 4: Simplify right side
   1,123.49x = 579,008.54
5. Step 5: Solve for x
   x = 579,008.54/1,123.49
6. Step 6: Final answer
   x = 515.37