Finding the Fourth Proportional to 807.78, 1,114.83 and 709.86

Step by Step Solution

1. Step 1: Write the proportion equation
   807.78 : 1,114.83 = 709.86 : x
2. Step 2: Convert to fraction form
   807.78/1,114.83 = 709.86/x
3. Step 3: Cross multiply
   807.78x = 1,114.83 × 709.86
4. Step 4: Simplify right side
   807.78x = 791,373.22
5. Step 5: Solve for x
   x = 791,373.22/807.78
6. Step 6: Final answer
   x = 979.69