Finding the Fourth Proportional to 89,839.78, 123,900.15 and 71,928.25

Step by Step Solution

1. Step 1: Write the proportion equation
   89,839.78 : 123,900.15 = 71,928.25 : x
2. Step 2: Convert to fraction form
   89,839.78/123,900.15 = 71,928.25/x
3. Step 3: Cross multiply
   89,839.78x = 123,900.15 × 71,928.25
4. Step 4: Simplify right side
   89,839.78x = 8,911,920,344.74
5. Step 5: Solve for x
   x = 8,911,920,344.74/89,839.78
6. Step 6: Final answer
   x = 99,197.94