Finding the Third Proportional to 216,155 and 345,312.50

Step by Step Solution

1. Step 1: Write the proportion equation
   216,155 : 345,312.50 = 345,312.50 : x
2. Step 2: Convert to fraction form
   216,155/345,312.50 = 345,312.50/x
3. Step 3: Cross multiply
   216,155x = 345,312.50 × 345,312.50
4. Step 4: Simplify right side
   216,155x = 119,240,722,656.25
5. Step 5: Solve for x
   x = 119,240,722,656.25/216,155
6. Step 6: Final answer
   x = 551,644.53