Finding the Fourth Proportional to 71,962.64, 99,309.72 and 40,128.12

Step by Step Solution

1. Step 1: Write the proportion equation
   71,962.64 : 99,309.72 = 40,128.12 : x
2. Step 2: Convert to fraction form
   71,962.64/99,309.72 = 40,128.12/x
3. Step 3: Cross multiply
   71,962.64x = 99,309.72 × 40,128.12
4. Step 4: Simplify right side
   71,962.64x = 3,985,112,361.33
5. Step 5: Solve for x
   x = 3,985,112,361.33/71,962.64
6. Step 6: Final answer
   x = 55,377.52