Finding the Fourth Proportional to 1,404.78, 1,938.71 and 815.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.78 : 1,938.71 = 815.27 : x
2. Step 2: Convert to fraction form
   1,404.78/1,938.71 = 815.27/x
3. Step 3: Cross multiply
   1,404.78x = 1,938.71 × 815.27
4. Step 4: Simplify right side
   1,404.78x = 1,580,578.51
5. Step 5: Solve for x
   x = 1,580,578.51/1,404.78
6. Step 6: Final answer
   x = 1,125.15