Finding the Fourth Proportional to 1,007.59, 1,390.45 and 559.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.59 : 1,390.45 = 559.46 : x
2. Step 2: Convert to fraction form
   1,007.59/1,390.45 = 559.46/x
3. Step 3: Cross multiply
   1,007.59x = 1,390.45 × 559.46
4. Step 4: Simplify right side
   1,007.59x = 777,902.15
5. Step 5: Solve for x
   x = 777,902.15/1,007.59
6. Step 6: Final answer
   x = 772.04