Finding the Fourth Proportional to 78,391.31, 117,738.23 and 67,172.00

Step by Step Solution

1. Step 1: Write the proportion equation
   78,391.31 : 117,738.23 = 67,172.00 : x
2. Step 2: Convert to fraction form
   78,391.31/117,738.23 = 67,172.00/x
3. Step 3: Cross multiply
   78,391.31x = 117,738.23 × 67,172.00
4. Step 4: Simplify right side
   78,391.31x = 7,908,711,461.01
5. Step 5: Solve for x
   x = 7,908,711,461.01/78,391.31
6. Step 6: Final answer
   x = 100,887.61