Finding the Fourth Proportional to 139,128.10, 191,996.76 and 78,697.44

Step by Step Solution

1. Step 1: Write the proportion equation
   139,128.10 : 191,996.76 = 78,697.44 : x
2. Step 2: Convert to fraction form
   139,128.10/191,996.76 = 78,697.44/x
3. Step 3: Cross multiply
   139,128.10x = 191,996.76 × 78,697.44
4. Step 4: Simplify right side
   139,128.10x = 15,109,653,500.29
5. Step 5: Solve for x
   x = 15,109,653,500.29/139,128.10
6. Step 6: Final answer
   x = 108,602.46