Finding the Third Proportional to 258,491.50 and 378,726

Step by Step Solution

1. Step 1: Write the proportion equation
   258,491.50 : 378,726 = 378,726 : x
2. Step 2: Convert to fraction form
   258,491.50/378,726 = 378,726/x
3. Step 3: Cross multiply
   258,491.50x = 378,726 × 378,726
4. Step 4: Simplify right side
   258,491.50x = 143,433,383,076
5. Step 5: Solve for x
   x = 143,433,383,076/258,491.50
6. Step 6: Final answer
   x = 554,886.27