Finding the Fourth Proportional to 153,729.50, 212,146.72 and 86,661.50

Step by Step Solution

1. Step 1: Write the proportion equation
   153,729.50 : 212,146.72 = 86,661.50 : x
2. Step 2: Convert to fraction form
   153,729.50/212,146.72 = 86,661.50/x
3. Step 3: Cross multiply
   153,729.50x = 212,146.72 × 86,661.50
4. Step 4: Simplify right side
   153,729.50x = 18,384,952,975.28
5. Step 5: Solve for x
   x = 18,384,952,975.28/153,729.50
6. Step 6: Final answer
   x = 119,592.88