Finding the Third Proportional to 57,429 and 86,688

Step by Step Solution

1. Step 1: Write the proportion equation
   57,429 : 86,688 = 86,688 : x
2. Step 2: Convert to fraction form
   57,429/86,688 = 86,688/x
3. Step 3: Cross multiply
   57,429x = 86,688 × 86,688
4. Step 4: Simplify right side
   57,429x = 7,514,809,344
5. Step 5: Solve for x
   x = 7,514,809,344/57,429
6. Step 6: Final answer
   x = 130,853.91