Finding the Fourth Proportional to 99,452.16, 137,247.20 and 57,018.72

Step by Step Solution

1. Step 1: Write the proportion equation
   99,452.16 : 137,247.20 = 57,018.72 : x
2. Step 2: Convert to fraction form
   99,452.16/137,247.20 = 57,018.72/x
3. Step 3: Cross multiply
   99,452.16x = 137,247.20 × 57,018.72
4. Step 4: Simplify right side
   99,452.16x = 7,825,659,667.58
5. Step 5: Solve for x
   x = 7,825,659,667.58/99,452.16
6. Step 6: Final answer
   x = 78,687.68