Finding the Fourth Proportional to 99,989.69, 138,020.52 and 57,565.13

Step by Step Solution

1. Step 1: Write the proportion equation
   99,989.69 : 138,020.52 = 57,565.13 : x
2. Step 2: Convert to fraction form
   99,989.69/138,020.52 = 57,565.13/x
3. Step 3: Cross multiply
   99,989.69x = 138,020.52 × 57,565.13
4. Step 4: Simplify right side
   99,989.69x = 7,945,169,176.47
5. Step 5: Solve for x
   x = 7,945,169,176.47/99,989.69
6. Step 6: Final answer
   x = 79,459.88