Finding the Fourth Proportional to 1,369.57, 1,889.78 and 809.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,369.57 : 1,889.78 = 809.96 : x
2. Step 2: Convert to fraction form
   1,369.57/1,889.78 = 809.96/x
3. Step 3: Cross multiply
   1,369.57x = 1,889.78 × 809.96
4. Step 4: Simplify right side
   1,369.57x = 1,530,646.21
5. Step 5: Solve for x
   x = 1,530,646.21/1,369.57
6. Step 6: Final answer
   x = 1,117.61