Finding the Third Proportional to 348,388.50 and 509,139

Step by Step Solution

1. Step 1: Write the proportion equation
   348,388.50 : 509,139 = 509,139 : x
2. Step 2: Convert to fraction form
   348,388.50/509,139 = 509,139/x
3. Step 3: Cross multiply
   348,388.50x = 509,139 × 509,139
4. Step 4: Simplify right side
   348,388.50x = 259,222,521,321
5. Step 5: Solve for x
   x = 259,222,521,321/348,388.50
6. Step 6: Final answer
   x = 744,061.65