Finding the Fourth Proportional to 10,121.78, 15,187.05 and 5,436.32

Step by Step Solution

1. Step 1: Write the proportion equation
   10,121.78 : 15,187.05 = 5,436.32 : x
2. Step 2: Convert to fraction form
   10,121.78/15,187.05 = 5,436.32/x
3. Step 3: Cross multiply
   10,121.78x = 15,187.05 × 5,436.32
4. Step 4: Simplify right side
   10,121.78x = 82,561,587.72
5. Step 5: Solve for x
   x = 82,561,587.72/10,121.78
6. Step 6: Final answer
   x = 8,156.83