Finding the Third Proportional to 138,938.50 and 215,272

Step by Step Solution

1. Step 1: Write the proportion equation
   138,938.50 : 215,272 = 215,272 : x
2. Step 2: Convert to fraction form
   138,938.50/215,272 = 215,272/x
3. Step 3: Cross multiply
   138,938.50x = 215,272 × 215,272
4. Step 4: Simplify right side
   138,938.50x = 46,342,033,984
5. Step 5: Solve for x
   x = 46,342,033,984/138,938.50
6. Step 6: Final answer
   x = 333,543.50