Finding the Fourth Proportional to 85,521.90, 128,436.45 and 82,757.10

Step by Step Solution

1. Step 1: Write the proportion equation
   85,521.90 : 128,436.45 = 82,757.10 : x
2. Step 2: Convert to fraction form
   85,521.90/128,436.45 = 82,757.10/x
3. Step 3: Cross multiply
   85,521.90x = 128,436.45 × 82,757.10
4. Step 4: Simplify right side
   85,521.90x = 10,629,028,136.30
5. Step 5: Solve for x
   x = 10,629,028,136.30/85,521.90
6. Step 6: Final answer
   x = 124,284.28