Finding the Fourth Proportional to 2,809.50, 4,216.17 and 985.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,809.50 : 4,216.17 = 985.50 : x
2. Step 2: Convert to fraction form
   2,809.50/4,216.17 = 985.50/x
3. Step 3: Cross multiply
   2,809.50x = 4,216.17 × 985.50
4. Step 4: Simplify right side
   2,809.50x = 4,155,035.54
5. Step 5: Solve for x
   x = 4,155,035.54/2,809.50
6. Step 6: Final answer
   x = 1,478.92