Finding the Fourth Proportional to 71,810.88, 99,096.72 and 39,978.16

Step by Step Solution

1. Step 1: Write the proportion equation
   71,810.88 : 99,096.72 = 39,978.16 : x
2. Step 2: Convert to fraction form
   71,810.88/99,096.72 = 39,978.16/x
3. Step 3: Cross multiply
   71,810.88x = 99,096.72 × 39,978.16
4. Step 4: Simplify right side
   71,810.88x = 3,961,704,527.64
5. Step 5: Solve for x
   x = 3,961,704,527.64/71,810.88
6. Step 6: Final answer
   x = 55,168.58