Finding the Third Proportional to 117,638 and 256,426

Step by Step Solution

1. Step 1: Write the proportion equation
   117,638 : 256,426 = 256,426 : x
2. Step 2: Convert to fraction form
   117,638/256,426 = 256,426/x
3. Step 3: Cross multiply
   117,638x = 256,426 × 256,426
4. Step 4: Simplify right side
   117,638x = 65,754,293,476
5. Step 5: Solve for x
   x = 65,754,293,476/117,638
6. Step 6: Final answer
   x = 558,954.53