Finding the Third Proportional to 258,916.50 and 555,129

Step by Step Solution

1. Step 1: Write the proportion equation
   258,916.50 : 555,129 = 555,129 : x
2. Step 2: Convert to fraction form
   258,916.50/555,129 = 555,129/x
3. Step 3: Cross multiply
   258,916.50x = 555,129 × 555,129
4. Step 4: Simplify right side
   258,916.50x = 308,168,206,641
5. Step 5: Solve for x
   x = 308,168,206,641/258,916.50
6. Step 6: Final answer
   x = 1,190,222.36