Finding the Fourth Proportional to 80,099.12, 120,166.90 and 42,639.45

Step by Step Solution

1. Step 1: Write the proportion equation
   80,099.12 : 120,166.90 = 42,639.45 : x
2. Step 2: Convert to fraction form
   80,099.12/120,166.90 = 42,639.45/x
3. Step 3: Cross multiply
   80,099.12x = 120,166.90 × 42,639.45
4. Step 4: Simplify right side
   80,099.12x = 5,123,851,280.70
5. Step 5: Solve for x
   x = 5,123,851,280.70/80,099.12
6. Step 6: Final answer
   x = 63,968.88