Finding the Fourth Proportional to 78,665.60, 108,557.99 and 42,855.64

Step by Step Solution

1. Step 1: Write the proportion equation
   78,665.60 : 108,557.99 = 42,855.64 : x
2. Step 2: Convert to fraction form
   78,665.60/108,557.99 = 42,855.64/x
3. Step 3: Cross multiply
   78,665.60x = 108,557.99 × 42,855.64
4. Step 4: Simplify right side
   78,665.60x = 4,652,322,138.56
5. Step 5: Solve for x
   x = 4,652,322,138.56/78,665.60
6. Step 6: Final answer
   x = 59,140.49