Finding the Fourth Proportional to 142,978.40, 214,469.15 and 43,139.48

Step by Step Solution

1. Step 1: Write the proportion equation
   142,978.40 : 214,469.15 = 43,139.48 : x
2. Step 2: Convert to fraction form
   142,978.40/214,469.15 = 43,139.48/x
3. Step 3: Cross multiply
   142,978.40x = 214,469.15 × 43,139.48
4. Step 4: Simplify right side
   142,978.40x = 9,252,087,607.04
5. Step 5: Solve for x
   x = 9,252,087,607.04/142,978.40
6. Step 6: Final answer
   x = 64,709.69