Finding the Fourth Proportional to 1,123.89, 1,686.55 and 546.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123.89 : 1,686.55 = 546.45 : x
2. Step 2: Convert to fraction form
   1,123.89/1,686.55 = 546.45/x
3. Step 3: Cross multiply
   1,123.89x = 1,686.55 × 546.45
4. Step 4: Simplify right side
   1,123.89x = 921,615.25
5. Step 5: Solve for x
   x = 921,615.25/1,123.89
6. Step 6: Final answer
   x = 820.02