Finding the Fourth Proportional to 1,405.04, 1,938.80 and 815.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.04 : 1,938.80 = 815.46 : x
2. Step 2: Convert to fraction form
   1,405.04/1,938.80 = 815.46/x
3. Step 3: Cross multiply
   1,405.04x = 1,938.80 × 815.46
4. Step 4: Simplify right side
   1,405.04x = 1,581,008.62
5. Step 5: Solve for x
   x = 1,581,008.62/1,405.04
6. Step 6: Final answer
   x = 1,125.25