Finding the Third Proportional to 213,115 and 355,141.50

Step by Step Solution

1. Step 1: Write the proportion equation
   213,115 : 355,141.50 = 355,141.50 : x
2. Step 2: Convert to fraction form
   213,115/355,141.50 = 355,141.50/x
3. Step 3: Cross multiply
   213,115x = 355,141.50 × 355,141.50
4. Step 4: Simplify right side
   213,115x = 126,125,485,022.25
5. Step 5: Solve for x
   x = 126,125,485,022.25/213,115
6. Step 6: Final answer
   x = 591,818.90