Finding the Fourth Proportional to 1,404.81, 1,938.87 and 815.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.81 : 1,938.87 = 815.67 : x
2. Step 2: Convert to fraction form
   1,404.81/1,938.87 = 815.67/x
3. Step 3: Cross multiply
   1,404.81x = 1,938.87 × 815.67
4. Step 4: Simplify right side
   1,404.81x = 1,581,478.09
5. Step 5: Solve for x
   x = 1,581,478.09/1,404.81
6. Step 6: Final answer
   x = 1,125.76