Finding the Fourth Proportional to 1,404.86, 1,938.60 and 815.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.86 : 1,938.60 = 815.45 : x
2. Step 2: Convert to fraction form
   1,404.86/1,938.60 = 815.45/x
3. Step 3: Cross multiply
   1,404.86x = 1,938.60 × 815.45
4. Step 4: Simplify right side
   1,404.86x = 1,580,821.68
5. Step 5: Solve for x
   x = 1,580,821.68/1,404.86
6. Step 6: Final answer
   x = 1,125.26