Finding the Fourth Proportional to 2,218.49, 3,061.50 and 1,223.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,218.49 : 3,061.50 = 1,223.78 : x
2. Step 2: Convert to fraction form
   2,218.49/3,061.50 = 1,223.78/x
3. Step 3: Cross multiply
   2,218.49x = 3,061.50 × 1,223.78
4. Step 4: Simplify right side
   2,218.49x = 3,746,602.47
5. Step 5: Solve for x
   x = 3,746,602.47/2,218.49
6. Step 6: Final answer
   x = 1,688.81