Finding the Third Proportional to 292,680 and 638,401.50

Step by Step Solution

1. Step 1: Write the proportion equation
   292,680 : 638,401.50 = 638,401.50 : x
2. Step 2: Convert to fraction form
   292,680/638,401.50 = 638,401.50/x
3. Step 3: Cross multiply
   292,680x = 638,401.50 × 638,401.50
4. Step 4: Simplify right side
   292,680x = 407,556,475,202.25
5. Step 5: Solve for x
   x = 407,556,475,202.25/292,680
6. Step 6: Final answer
   x = 1,392,498.55