Finding the Third Proportional to 76,389 and 99,808.50

Step by Step Solution

1. Step 1: Write the proportion equation
   76,389 : 99,808.50 = 99,808.50 : x
2. Step 2: Convert to fraction form
   76,389/99,808.50 = 99,808.50/x
3. Step 3: Cross multiply
   76,389x = 99,808.50 × 99,808.50
4. Step 4: Simplify right side
   76,389x = 9,961,736,672.25
5. Step 5: Solve for x
   x = 9,961,736,672.25/76,389
6. Step 6: Final answer
   x = 130,408.00