Finding the Third Proportional to 129,280 and 200,064

Step by Step Solution

1. Step 1: Write the proportion equation
   129,280 : 200,064 = 200,064 : x
2. Step 2: Convert to fraction form
   129,280/200,064 = 200,064/x
3. Step 3: Cross multiply
   129,280x = 200,064 × 200,064
4. Step 4: Simplify right side
   129,280x = 40,025,604,096
5. Step 5: Solve for x
   x = 40,025,604,096/129,280
6. Step 6: Final answer
   x = 309,603.99