Finding the Fourth Proportional to 65,286.13, 89,508.11 and 64,105.15

Step by Step Solution

1. Step 1: Write the proportion equation
   65,286.13 : 89,508.11 = 64,105.15 : x
2. Step 2: Convert to fraction form
   65,286.13/89,508.11 = 64,105.15/x
3. Step 3: Cross multiply
   65,286.13x = 89,508.11 × 64,105.15
4. Step 4: Simplify right side
   65,286.13x = 5,737,930,978.03
5. Step 5: Solve for x
   x = 5,737,930,978.03/65,286.13
6. Step 6: Final answer
   x = 87,888.97