Finding the Fourth Proportional to 108,420.12, 149,705.82 and 72,156.42

Step by Step Solution

1. Step 1: Write the proportion equation
   108,420.12 : 149,705.82 = 72,156.42 : x
2. Step 2: Convert to fraction form
   108,420.12/149,705.82 = 72,156.42/x
3. Step 3: Cross multiply
   108,420.12x = 149,705.82 × 72,156.42
4. Step 4: Simplify right side
   108,420.12x = 10,802,236,024.36
5. Step 5: Solve for x
   x = 10,802,236,024.36/108,420.12
6. Step 6: Final answer
   x = 99,633.13