Finding the Fourth Proportional to 128,061.72, 192,190.56 and 57,990.24

Step by Step Solution

1. Step 1: Write the proportion equation
   128,061.72 : 192,190.56 = 57,990.24 : x
2. Step 2: Convert to fraction form
   128,061.72/192,190.56 = 57,990.24/x
3. Step 3: Cross multiply
   128,061.72x = 192,190.56 × 57,990.24
4. Step 4: Simplify right side
   128,061.72x = 11,145,176,700.13
5. Step 5: Solve for x
   x = 11,145,176,700.13/128,061.72
6. Step 6: Final answer
   x = 87,029.73