Finding the Third Proportional to 78,229.50 and 109,678.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,229.50 : 109,678.50 = 109,678.50 : x
2. Step 2: Convert to fraction form
   78,229.50/109,678.50 = 109,678.50/x
3. Step 3: Cross multiply
   78,229.50x = 109,678.50 × 109,678.50
4. Step 4: Simplify right side
   78,229.50x = 12,029,373,362.25
5. Step 5: Solve for x
   x = 12,029,373,362.25/78,229.50
6. Step 6: Final answer
   x = 153,770.30