Finding the Third Proportional to 139,456 and 288,128

Step by Step Solution

1. Step 1: Write the proportion equation
   139,456 : 288,128 = 288,128 : x
2. Step 2: Convert to fraction form
   139,456/288,128 = 288,128/x
3. Step 3: Cross multiply
   139,456x = 288,128 × 288,128
4. Step 4: Simplify right side
   139,456x = 83,017,744,384
5. Step 5: Solve for x
   x = 83,017,744,384/139,456
6. Step 6: Final answer
   x = 595,297.04