Finding the Fourth Proportional to 86,402.70, 129,472.56 and 64,111.50

Step by Step Solution

1. Step 1: Write the proportion equation
   86,402.70 : 129,472.56 = 64,111.50 : x
2. Step 2: Convert to fraction form
   86,402.70/129,472.56 = 64,111.50/x
3. Step 3: Cross multiply
   86,402.70x = 129,472.56 × 64,111.50
4. Step 4: Simplify right side
   86,402.70x = 8,300,680,030.44
5. Step 5: Solve for x
   x = 8,300,680,030.44/86,402.70
6. Step 6: Final answer
   x = 96,069.68