Finding the Fourth Proportional to 142,708.77, 196,978.64 and 86,123.79

Step by Step Solution

1. Step 1: Write the proportion equation
   142,708.77 : 196,978.64 = 86,123.79 : x
2. Step 2: Convert to fraction form
   142,708.77/196,978.64 = 86,123.79/x
3. Step 3: Cross multiply
   142,708.77x = 196,978.64 × 86,123.79
4. Step 4: Simplify right side
   142,708.77x = 16,964,546,595.23
5. Step 5: Solve for x
   x = 16,964,546,595.23/142,708.77
6. Step 6: Final answer
   x = 118,875.29