Finding the Fourth Proportional to 1,134.69, 1,566.05 and 780.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,134.69 : 1,566.05 = 780.31 : x
2. Step 2: Convert to fraction form
   1,134.69/1,566.05 = 780.31/x
3. Step 3: Cross multiply
   1,134.69x = 1,566.05 × 780.31
4. Step 4: Simplify right side
   1,134.69x = 1,222,006.92
5. Step 5: Solve for x
   x = 1,222,006.92/1,134.69
6. Step 6: Final answer
   x = 1,076.96