Finding the Fourth Proportional to 89,160.71, 133,907.67 and 78,490.89

Step by Step Solution

1. Step 1: Write the proportion equation
   89,160.71 : 133,907.67 = 78,490.89 : x
2. Step 2: Convert to fraction form
   89,160.71/133,907.67 = 78,490.89/x
3. Step 3: Cross multiply
   89,160.71x = 133,907.67 × 78,490.89
4. Step 4: Simplify right side
   89,160.71x = 10,510,532,196.13
5. Step 5: Solve for x
   x = 10,510,532,196.13/89,160.71
6. Step 6: Final answer
   x = 117,883.01