Finding the Third Proportional to 31,780.50 and 69,909

Step by Step Solution

1. Step 1: Write the proportion equation
   31,780.50 : 69,909 = 69,909 : x
2. Step 2: Convert to fraction form
   31,780.50/69,909 = 69,909/x
3. Step 3: Cross multiply
   31,780.50x = 69,909 × 69,909
4. Step 4: Simplify right side
   31,780.50x = 4,887,268,281
5. Step 5: Solve for x
   x = 4,887,268,281/31,780.50
6. Step 6: Final answer
   x = 153,781.98