Finding the Fourth Proportional to 978.54, 1,350.05 and 558.59

Step by Step Solution

1. Step 1: Write the proportion equation
   978.54 : 1,350.05 = 558.59 : x
2. Step 2: Convert to fraction form
   978.54/1,350.05 = 558.59/x
3. Step 3: Cross multiply
   978.54x = 1,350.05 × 558.59
4. Step 4: Simplify right side
   978.54x = 754,114.89
5. Step 5: Solve for x
   x = 754,114.89/978.54
6. Step 6: Final answer
   x = 770.65