Finding the Fourth Proportional to 1,409.63, 1,945.30 and 780.17

Step by Step Solution

1. Step 1: Write the proportion equation
   1,409.63 : 1,945.30 = 780.17 : x
2. Step 2: Convert to fraction form
   1,409.63/1,945.30 = 780.17/x
3. Step 3: Cross multiply
   1,409.63x = 1,945.30 × 780.17
4. Step 4: Simplify right side
   1,409.63x = 1,517,653.02
5. Step 5: Solve for x
   x = 1,517,653.02/1,409.63
6. Step 6: Final answer
   x = 1,076.64