Finding the Third Proportional to 77,991 and 108,664.50

Step by Step Solution

1. Step 1: Write the proportion equation
   77,991 : 108,664.50 = 108,664.50 : x
2. Step 2: Convert to fraction form
   77,991/108,664.50 = 108,664.50/x
3. Step 3: Cross multiply
   77,991x = 108,664.50 × 108,664.50
4. Step 4: Simplify right side
   77,991x = 11,807,973,560.25
5. Step 5: Solve for x
   x = 11,807,973,560.25/77,991
6. Step 6: Final answer
   x = 151,401.75