Finding the Fourth Proportional to 1,409.55, 1,945.31 and 780.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,409.55 : 1,945.31 = 780.23 : x
2. Step 2: Convert to fraction form
   1,409.55/1,945.31 = 780.23/x
3. Step 3: Cross multiply
   1,409.55x = 1,945.31 × 780.23
4. Step 4: Simplify right side
   1,409.55x = 1,517,775.59
5. Step 5: Solve for x
   x = 1,517,775.59/1,409.55
6. Step 6: Final answer
   x = 1,076.78