Finding the Fourth Proportional to 71,810.46, 99,096.75 and 39,978.72

Step by Step Solution

1. Step 1: Write the proportion equation
   71,810.46 : 99,096.75 = 39,978.72 : x
2. Step 2: Convert to fraction form
   71,810.46/99,096.75 = 39,978.72/x
3. Step 3: Cross multiply
   71,810.46x = 99,096.75 × 39,978.72
4. Step 4: Simplify right side
   71,810.46x = 3,961,761,221.16
5. Step 5: Solve for x
   x = 3,961,761,221.16/71,810.46
6. Step 6: Final answer
   x = 55,169.70