Finding the Third Proportional to 98,638 and 213,042.50

Step by Step Solution

1. Step 1: Write the proportion equation
   98,638 : 213,042.50 = 213,042.50 : x
2. Step 2: Convert to fraction form
   98,638/213,042.50 = 213,042.50/x
3. Step 3: Cross multiply
   98,638x = 213,042.50 × 213,042.50
4. Step 4: Simplify right side
   98,638x = 45,387,106,806.25
5. Step 5: Solve for x
   x = 45,387,106,806.25/98,638
6. Step 6: Final answer
   x = 460,138.15