Finding the Fourth Proportional to 89,431, 123,414.78 and 51,707.68

Step by Step Solution

1. Step 1: Write the proportion equation
   89,431 : 123,414.78 = 51,707.68 : x
2. Step 2: Convert to fraction form
   89,431/123,414.78 = 51,707.68/x
3. Step 3: Cross multiply
   89,431x = 123,414.78 × 51,707.68
4. Step 4: Simplify right side
   89,431x = 6,381,491,951.51
5. Step 5: Solve for x
   x = 6,381,491,951.51/89,431
6. Step 6: Final answer
   x = 71,356.60