Finding the Third Proportional to 39,420 and 86,505.75

Step by Step Solution

1. Step 1: Write the proportion equation
   39,420 : 86,505.75 = 86,505.75 : x
2. Step 2: Convert to fraction form
   39,420/86,505.75 = 86,505.75/x
3. Step 3: Cross multiply
   39,420x = 86,505.75 × 86,505.75
4. Step 4: Simplify right side
   39,420x = 7,483,244,783.06
5. Step 5: Solve for x
   x = 7,483,244,783.06/39,420
6. Step 6: Final answer
   x = 189,833.71