Finding the Fourth Proportional to 105,978.72, 158,968.16 and 39,417.60

Step by Step Solution

1. Step 1: Write the proportion equation
   105,978.72 : 158,968.16 = 39,417.60 : x
2. Step 2: Convert to fraction form
   105,978.72/158,968.16 = 39,417.60/x
3. Step 3: Cross multiply
   105,978.72x = 158,968.16 × 39,417.60
4. Step 4: Simplify right side
   105,978.72x = 6,266,143,343.62
5. Step 5: Solve for x
   x = 6,266,143,343.62/105,978.72
6. Step 6: Final answer
   x = 59,126.43