Finding the Third Proportional to 212,203 and 288,367.50

Step by Step Solution

1. Step 1: Write the proportion equation
   212,203 : 288,367.50 = 288,367.50 : x
2. Step 2: Convert to fraction form
   212,203/288,367.50 = 288,367.50/x
3. Step 3: Cross multiply
   212,203x = 288,367.50 × 288,367.50
4. Step 4: Simplify right side
   212,203x = 83,155,815,056.25
5. Step 5: Solve for x
   x = 83,155,815,056.25/212,203
6. Step 6: Final answer
   x = 391,869.18