Finding the Third Proportional to 30,820.50 and 68,809.50

Step by Step Solution

1. Step 1: Write the proportion equation
   30,820.50 : 68,809.50 = 68,809.50 : x
2. Step 2: Convert to fraction form
   30,820.50/68,809.50 = 68,809.50/x
3. Step 3: Cross multiply
   30,820.50x = 68,809.50 × 68,809.50
4. Step 4: Simplify right side
   30,820.50x = 4,734,747,290.25
5. Step 5: Solve for x
   x = 4,734,747,290.25/30,820.50
6. Step 6: Final answer
   x = 153,623.31