Finding the Fourth Proportional to 115,290.50, 159,100.89 and 64,989.50

Step by Step Solution

1. Step 1: Write the proportion equation
   115,290.50 : 159,100.89 = 64,989.50 : x
2. Step 2: Convert to fraction form
   115,290.50/159,100.89 = 64,989.50/x
3. Step 3: Cross multiply
   115,290.50x = 159,100.89 × 64,989.50
4. Step 4: Simplify right side
   115,290.50x = 10,339,887,290.66
5. Step 5: Solve for x
   x = 10,339,887,290.66/115,290.50
6. Step 6: Final answer
   x = 89,685.51