Finding the Third Proportional to 57,129 and 123,789

Step by Step Solution

1. Step 1: Write the proportion equation
   57,129 : 123,789 = 123,789 : x
2. Step 2: Convert to fraction form
   57,129/123,789 = 123,789/x
3. Step 3: Cross multiply
   57,129x = 123,789 × 123,789
4. Step 4: Simplify right side
   57,129x = 15,323,716,521
5. Step 5: Solve for x
   x = 15,323,716,521/57,129
6. Step 6: Final answer
   x = 268,230.08