Finding the Fourth Proportional to 1,007.94, 1,390.93 and 565.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.94 : 1,390.93 = 565.86 : x
2. Step 2: Convert to fraction form
   1,007.94/1,390.93 = 565.86/x
3. Step 3: Cross multiply
   1,007.94x = 1,390.93 × 565.86
4. Step 4: Simplify right side
   1,007.94x = 787,068.82
5. Step 5: Solve for x
   x = 787,068.82/1,007.94
6. Step 6: Final answer
   x = 780.87