Finding the Third Proportional to 85,724 and 186,128

Step by Step Solution

1. Step 1: Write the proportion equation
   85,724 : 186,128 = 186,128 : x
2. Step 2: Convert to fraction form
   85,724/186,128 = 186,128/x
3. Step 3: Cross multiply
   85,724x = 186,128 × 186,128
4. Step 4: Simplify right side
   85,724x = 34,643,632,384
5. Step 5: Solve for x
   x = 34,643,632,384/85,724
6. Step 6: Final answer
   x = 404,129.91