Finding the Fourth Proportional to 12,678.32, 19,018.56 and 3,318.30

Step by Step Solution

1. Step 1: Write the proportion equation
   12,678.32 : 19,018.56 = 3,318.30 : x
2. Step 2: Convert to fraction form
   12,678.32/19,018.56 = 3,318.30/x
3. Step 3: Cross multiply
   12,678.32x = 19,018.56 × 3,318.30
4. Step 4: Simplify right side
   12,678.32x = 63,109,287.65
5. Step 5: Solve for x
   x = 63,109,287.65/12,678.32
6. Step 6: Final answer
   x = 4,977.73