Finding the Third Proportional to 139,438 and 210,468

Step by Step Solution

1. Step 1: Write the proportion equation
   139,438 : 210,468 = 210,468 : x
2. Step 2: Convert to fraction form
   139,438/210,468 = 210,468/x
3. Step 3: Cross multiply
   139,438x = 210,468 × 210,468
4. Step 4: Simplify right side
   139,438x = 44,296,779,024
5. Step 5: Solve for x
   x = 44,296,779,024/139,438
6. Step 6: Final answer
   x = 317,680.83