Finding the Third Proportional to 305,131.50 and 638,145

Step by Step Solution

1. Step 1: Write the proportion equation
   305,131.50 : 638,145 = 638,145 : x
2. Step 2: Convert to fraction form
   305,131.50/638,145 = 638,145/x
3. Step 3: Cross multiply
   305,131.50x = 638,145 × 638,145
4. Step 4: Simplify right side
   305,131.50x = 407,229,041,025
5. Step 5: Solve for x
   x = 407,229,041,025/305,131.50
6. Step 6: Final answer
   x = 1,334,601.77