Finding the Fourth Proportional to 1,433.81, 1,978.66 and 812.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,433.81 : 1,978.66 = 812.81 : x
2. Step 2: Convert to fraction form
   1,433.81/1,978.66 = 812.81/x
3. Step 3: Cross multiply
   1,433.81x = 1,978.66 × 812.81
4. Step 4: Simplify right side
   1,433.81x = 1,608,280.60
5. Step 5: Solve for x
   x = 1,608,280.60/1,433.81
6. Step 6: Final answer
   x = 1,121.68