Finding the Third Proportional to 259,169 and 423,199.50

Step by Step Solution

1. Step 1: Write the proportion equation
   259,169 : 423,199.50 = 423,199.50 : x
2. Step 2: Convert to fraction form
   259,169/423,199.50 = 423,199.50/x
3. Step 3: Cross multiply
   259,169x = 423,199.50 × 423,199.50
4. Step 4: Simplify right side
   259,169x = 179,097,816,800.25
5. Step 5: Solve for x
   x = 179,097,816,800.25/259,169
6. Step 6: Final answer
   x = 691,046.45