Finding the Fourth Proportional to 1,217.98, 1,825.63 and 779.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,217.98 : 1,825.63 = 779.50 : x
2. Step 2: Convert to fraction form
   1,217.98/1,825.63 = 779.50/x
3. Step 3: Cross multiply
   1,217.98x = 1,825.63 × 779.50
4. Step 4: Simplify right side
   1,217.98x = 1,423,078.59
5. Step 5: Solve for x
   x = 1,423,078.59/1,217.98
6. Step 6: Final answer
   x = 1,168.39