Finding the Third Proportional to 249,481.50 and 390,912

Step by Step Solution

1. Step 1: Write the proportion equation
   249,481.50 : 390,912 = 390,912 : x
2. Step 2: Convert to fraction form
   249,481.50/390,912 = 390,912/x
3. Step 3: Cross multiply
   249,481.50x = 390,912 × 390,912
4. Step 4: Simplify right side
   249,481.50x = 152,812,191,744
5. Step 5: Solve for x
   x = 152,812,191,744/249,481.50
6. Step 6: Final answer
   x = 612,519.13