Finding the Third Proportional to 128,425 and 170,406.50

Step by Step Solution

1. Step 1: Write the proportion equation
   128,425 : 170,406.50 = 170,406.50 : x
2. Step 2: Convert to fraction form
   128,425/170,406.50 = 170,406.50/x
3. Step 3: Cross multiply
   128,425x = 170,406.50 × 170,406.50
4. Step 4: Simplify right side
   128,425x = 29,038,375,242.25
5. Step 5: Solve for x
   x = 29,038,375,242.25/128,425
6. Step 6: Final answer
   x = 226,111.55