Finding the Fourth Proportional to 89,437.20, 123,435 and 57,698.39

Step by Step Solution

1. Step 1: Write the proportion equation
   89,437.20 : 123,435 = 57,698.39 : x
2. Step 2: Convert to fraction form
   89,437.20/123,435 = 57,698.39/x
3. Step 3: Cross multiply
   89,437.20x = 123,435 × 57,698.39
4. Step 4: Simplify right side
   89,437.20x = 7,122,000,152.48
5. Step 5: Solve for x
   x = 7,122,000,152.48/89,437.20
6. Step 6: Final answer
   x = 79,631.30