Finding the Third Proportional to 142,638 and 199,434

Step by Step Solution

1. Step 1: Write the proportion equation
   142,638 : 199,434 = 199,434 : x
2. Step 2: Convert to fraction form
   142,638/199,434 = 199,434/x
3. Step 3: Cross multiply
   142,638x = 199,434 × 199,434
4. Step 4: Simplify right side
   142,638x = 39,773,920,356
5. Step 5: Solve for x
   x = 39,773,920,356/142,638
6. Step 6: Final answer
   x = 278,845.19