Finding the Fourth Proportional to 85,608.24, 128,419.38 and 42,898.56

Step by Step Solution

1. Step 1: Write the proportion equation
   85,608.24 : 128,419.38 = 42,898.56 : x
2. Step 2: Convert to fraction form
   85,608.24/128,419.38 = 42,898.56/x
3. Step 3: Cross multiply
   85,608.24x = 128,419.38 × 42,898.56
4. Step 4: Simplify right side
   85,608.24x = 5,509,006,478.09
5. Step 5: Solve for x
   x = 5,509,006,478.09/85,608.24
6. Step 6: Final answer
   x = 64,351.36