Finding the Third Proportional to 139,872 and 215,118

Step by Step Solution

1. Step 1: Write the proportion equation
   139,872 : 215,118 = 215,118 : x
2. Step 2: Convert to fraction form
   139,872/215,118 = 215,118/x
3. Step 3: Cross multiply
   139,872x = 215,118 × 215,118
4. Step 4: Simplify right side
   139,872x = 46,275,753,924
5. Step 5: Solve for x
   x = 46,275,753,924/139,872
6. Step 6: Final answer
   x = 330,843.59