Finding the Fourth Proportional to 2,168.78, 2,992.69 and 1,224.49

Step by Step Solution

1. Step 1: Write the proportion equation
   2,168.78 : 2,992.69 = 1,224.49 : x
2. Step 2: Convert to fraction form
   2,168.78/2,992.69 = 1,224.49/x
3. Step 3: Cross multiply
   2,168.78x = 2,992.69 × 1,224.49
4. Step 4: Simplify right side
   2,168.78x = 3,664,518.98
5. Step 5: Solve for x
   x = 3,664,518.98/2,168.78
6. Step 6: Final answer
   x = 1,689.67