Finding the Third Proportional to 54,158 and 86,499

Step by Step Solution

1. Step 1: Write the proportion equation
   54,158 : 86,499 = 86,499 : x
2. Step 2: Convert to fraction form
   54,158/86,499 = 86,499/x
3. Step 3: Cross multiply
   54,158x = 86,499 × 86,499
4. Step 4: Simplify right side
   54,158x = 7,482,077,001
5. Step 5: Solve for x
   x = 7,482,077,001/54,158
6. Step 6: Final answer
   x = 138,152.76