Finding the Third Proportional to 82,839 and 129,172.50

Step by Step Solution

1. Step 1: Write the proportion equation
   82,839 : 129,172.50 = 129,172.50 : x
2. Step 2: Convert to fraction form
   82,839/129,172.50 = 129,172.50/x
3. Step 3: Cross multiply
   82,839x = 129,172.50 × 129,172.50
4. Step 4: Simplify right side
   82,839x = 16,685,534,756.25
5. Step 5: Solve for x
   x = 16,685,534,756.25/82,839
6. Step 6: Final answer
   x = 201,421.25