Finding the Third Proportional to 216,153 and 345,309.50

Step by Step Solution

1. Step 1: Write the proportion equation
   216,153 : 345,309.50 = 345,309.50 : x
2. Step 2: Convert to fraction form
   216,153/345,309.50 = 345,309.50/x
3. Step 3: Cross multiply
   216,153x = 345,309.50 × 345,309.50
4. Step 4: Simplify right side
   216,153x = 119,238,650,790.25
5. Step 5: Solve for x
   x = 119,238,650,790.25/216,153
6. Step 6: Final answer
   x = 551,640.05