Finding the Third Proportional to 39,390.47 and 86,434.59

Step by Step Solution

1. Step 1: Write the proportion equation
   39,390.47 : 86,434.59 = 86,434.59 : x
2. Step 2: Convert to fraction form
   39,390.47/86,434.59 = 86,434.59/x
3. Step 3: Cross multiply
   39,390.47x = 86,434.59 × 86,434.59
4. Step 4: Simplify right side
   39,390.47x = 7,470,938,996.73
5. Step 5: Solve for x
   x = 7,470,938,996.73/39,390.47
6. Step 6: Final answer
   x = 189,663.62