Finding the Fourth Proportional to 60,639.10, 85,069.70 and 60,639.10

Step by Step Solution

1. Step 1: Write the proportion equation
   60,639.10 : 85,069.70 = 60,639.10 : x
2. Step 2: Convert to fraction form
   60,639.10/85,069.70 = 60,639.10/x
3. Step 3: Cross multiply
   60,639.10x = 85,069.70 × 60,639.10
4. Step 4: Simplify right side
   60,639.10x = 5,158,550,045.27
5. Step 5: Solve for x
   x = 5,158,550,045.27/60,639.10
6. Step 6: Final answer
   x = 85,069.70