Finding the Fourth Proportional to 1,223.84, 1,688.88 and 726.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,223.84 : 1,688.88 = 726.50 : x
2. Step 2: Convert to fraction form
   1,223.84/1,688.88 = 726.50/x
3. Step 3: Cross multiply
   1,223.84x = 1,688.88 × 726.50
4. Step 4: Simplify right side
   1,223.84x = 1,226,962.88
5. Step 5: Solve for x
   x = 1,226,962.88/1,223.84
6. Step 6: Final answer
   x = 1,002.56