Finding the Fourth Proportional to 1,206.60, 1,665.61 and 814.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,206.60 : 1,665.61 = 814.15 : x
2. Step 2: Convert to fraction form
   1,206.60/1,665.61 = 814.15/x
3. Step 3: Cross multiply
   1,206.60x = 1,665.61 × 814.15
4. Step 4: Simplify right side
   1,206.60x = 1,356,061.01
5. Step 5: Solve for x
   x = 1,356,061.01/1,206.60
6. Step 6: Final answer
   x = 1,123.87