Finding the Fourth Proportional to 100,139.34, 138,192.57 and 55,427.34

Step by Step Solution

1. Step 1: Write the proportion equation
   100,139.34 : 138,192.57 = 55,427.34 : x
2. Step 2: Convert to fraction form
   100,139.34/138,192.57 = 55,427.34/x
3. Step 3: Cross multiply
   100,139.34x = 138,192.57 × 55,427.34
4. Step 4: Simplify right side
   100,139.34x = 7,659,646,562.86
5. Step 5: Solve for x
   x = 7,659,646,562.86/100,139.34
6. Step 6: Final answer
   x = 76,489.88