Finding the Third Proportional to 138,856 and 298,784

Step by Step Solution

1. Step 1: Write the proportion equation
   138,856 : 298,784 = 298,784 : x
2. Step 2: Convert to fraction form
   138,856/298,784 = 298,784/x
3. Step 3: Cross multiply
   138,856x = 298,784 × 298,784
4. Step 4: Simplify right side
   138,856x = 89,271,878,656
5. Step 5: Solve for x
   x = 89,271,878,656/138,856
6. Step 6: Final answer
   x = 642,909.77