Finding the Third Proportional to 212,272.50 and 288,438

Step by Step Solution

1. Step 1: Write the proportion equation
   212,272.50 : 288,438 = 288,438 : x
2. Step 2: Convert to fraction form
   212,272.50/288,438 = 288,438/x
3. Step 3: Cross multiply
   212,272.50x = 288,438 × 288,438
4. Step 4: Simplify right side
   212,272.50x = 83,196,479,844
5. Step 5: Solve for x
   x = 83,196,479,844/212,272.50
6. Step 6: Final answer
   x = 391,932.44