Finding the Third Proportional to 310,881.38 and 645,131.25

Step by Step Solution

1. Step 1: Write the proportion equation
   310,881.38 : 645,131.25 = 645,131.25 : x
2. Step 2: Convert to fraction form
   310,881.38/645,131.25 = 645,131.25/x
3. Step 3: Cross multiply
   310,881.38x = 645,131.25 × 645,131.25
4. Step 4: Simplify right side
   310,881.38x = 416,194,329,726.56
5. Step 5: Solve for x
   x = 416,194,329,726.56/310,881.38
6. Step 6: Final answer
   x = 1,338,756.08