Finding the Third Proportional to 38,638.69 and 81,428.63

Step by Step Solution

1. Step 1: Write the proportion equation
   38,638.69 : 81,428.63 = 81,428.63 : x
2. Step 2: Convert to fraction form
   38,638.69/81,428.63 = 81,428.63/x
3. Step 3: Cross multiply
   38,638.69x = 81,428.63 × 81,428.63
4. Step 4: Simplify right side
   38,638.69x = 6,630,620,969.39
5. Step 5: Solve for x
   x = 6,630,620,969.39/38,638.69
6. Step 6: Final answer
   x = 171,605.75