Finding the Third Proportional to 138,940.50 and 215,275.50

Step by Step Solution

1. Step 1: Write the proportion equation
   138,940.50 : 215,275.50 = 215,275.50 : x
2. Step 2: Convert to fraction form
   138,940.50/215,275.50 = 215,275.50/x
3. Step 3: Cross multiply
   138,940.50x = 215,275.50 × 215,275.50
4. Step 4: Simplify right side
   138,940.50x = 46,343,540,900.25
5. Step 5: Solve for x
   x = 46,343,540,900.25/138,940.50
6. Step 6: Final answer
   x = 333,549.55