Finding the Third Proportional to 128,443.50 and 170,429.25

Step by Step Solution

1. Step 1: Write the proportion equation
   128,443.50 : 170,429.25 = 170,429.25 : x
2. Step 2: Convert to fraction form
   128,443.50/170,429.25 = 170,429.25/x
3. Step 3: Cross multiply
   128,443.50x = 170,429.25 × 170,429.25
4. Step 4: Simplify right side
   128,443.50x = 29,046,129,255.56
5. Step 5: Solve for x
   x = 29,046,129,255.56/128,443.50
6. Step 6: Final answer
   x = 226,139.35