Finding the Fourth Proportional to 1,636.91, 2,456.38 and 857.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,636.91 : 2,456.38 = 857.52 : x
2. Step 2: Convert to fraction form
   1,636.91/2,456.38 = 857.52/x
3. Step 3: Cross multiply
   1,636.91x = 2,456.38 × 857.52
4. Step 4: Simplify right side
   1,636.91x = 2,106,401.59
5. Step 5: Solve for x
   x = 2,106,401.59/1,636.91
6. Step 6: Final answer
   x = 1,286.82