Finding the Fourth Proportional to 12,678.78, 19,013.51 and 4,356.43

Step by Step Solution

1. Step 1: Write the proportion equation
   12,678.78 : 19,013.51 = 4,356.43 : x
2. Step 2: Convert to fraction form
   12,678.78/19,013.51 = 4,356.43/x
3. Step 3: Cross multiply
   12,678.78x = 19,013.51 × 4,356.43
4. Step 4: Simplify right side
   12,678.78x = 82,831,003.59
5. Step 5: Solve for x
   x = 82,831,003.59/12,678.78
6. Step 6: Final answer
   x = 6,533.04