Finding the Fourth Proportional to 1,406.11, 1,939.78 and 816.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,406.11 : 1,939.78 = 816.53 : x
2. Step 2: Convert to fraction form
   1,406.11/1,939.78 = 816.53/x
3. Step 3: Cross multiply
   1,406.11x = 1,939.78 × 816.53
4. Step 4: Simplify right side
   1,406.11x = 1,583,881.46
5. Step 5: Solve for x
   x = 1,583,881.46/1,406.11
6. Step 6: Final answer
   x = 1,126.43