Finding the Fourth Proportional to 89,420.28, 123,359.40 and 55,419.72

Step by Step Solution

1. Step 1: Write the proportion equation
   89,420.28 : 123,359.40 = 55,419.72 : x
2. Step 2: Convert to fraction form
   89,420.28/123,359.40 = 55,419.72/x
3. Step 3: Cross multiply
   89,420.28x = 123,359.40 × 55,419.72
4. Step 4: Simplify right side
   89,420.28x = 6,836,543,407.37
5. Step 5: Solve for x
   x = 6,836,543,407.37/89,420.28
6. Step 6: Final answer
   x = 76,454.06