Finding the Third Proportional to 386,388 and 837,128.50

Step by Step Solution

1. Step 1: Write the proportion equation
   386,388 : 837,128.50 = 837,128.50 : x
2. Step 2: Convert to fraction form
   386,388/837,128.50 = 837,128.50/x
3. Step 3: Cross multiply
   386,388x = 837,128.50 × 837,128.50
4. Step 4: Simplify right side
   386,388x = 700,784,125,512.25
5. Step 5: Solve for x
   x = 700,784,125,512.25/386,388
6. Step 6: Final answer
   x = 1,813,679.84