Finding the Fourth Proportional to 115,667.20, 159,621 and 64,681.76

Step by Step Solution

1. Step 1: Write the proportion equation
   115,667.20 : 159,621 = 64,681.76 : x
2. Step 2: Convert to fraction form
   115,667.20/159,621 = 64,681.76/x
3. Step 3: Cross multiply
   115,667.20x = 159,621 × 64,681.76
4. Step 4: Simplify right side
   115,667.20x = 10,324,567,212.96
5. Step 5: Solve for x
   x = 10,324,567,212.96/115,667.20
6. Step 6: Final answer
   x = 89,260.98