Finding the Third Proportional to 213,111 and 355,135.50

Step by Step Solution

1. Step 1: Write the proportion equation
   213,111 : 355,135.50 = 355,135.50 : x
2. Step 2: Convert to fraction form
   213,111/355,135.50 = 355,135.50/x
3. Step 3: Cross multiply
   213,111x = 355,135.50 × 355,135.50
4. Step 4: Simplify right side
   213,111x = 126,121,223,360.25
5. Step 5: Solve for x
   x = 126,121,223,360.25/213,111
6. Step 6: Final answer
   x = 591,810.01