Finding the Third Proportional to 258,355.50 and 379,878

Step by Step Solution

1. Step 1: Write the proportion equation
   258,355.50 : 379,878 = 379,878 : x
2. Step 2: Convert to fraction form
   258,355.50/379,878 = 379,878/x
3. Step 3: Cross multiply
   258,355.50x = 379,878 × 379,878
4. Step 4: Simplify right side
   258,355.50x = 144,307,294,884
5. Step 5: Solve for x
   x = 144,307,294,884/258,355.50
6. Step 6: Final answer
   x = 558,560.96