Finding the Fourth Proportional to 123,121.16, 169,907.78 and 72,142.96

Step by Step Solution

1. Step 1: Write the proportion equation
   123,121.16 : 169,907.78 = 72,142.96 : x
2. Step 2: Convert to fraction form
   123,121.16/169,907.78 = 72,142.96/x
3. Step 3: Cross multiply
   123,121.16x = 169,907.78 × 72,142.96
4. Step 4: Simplify right side
   123,121.16x = 12,257,650,176.23
5. Step 5: Solve for x
   x = 12,257,650,176.23/123,121.16
6. Step 6: Final answer
   x = 99,557.62