Finding the Third Proportional to 78,723 and 123,138

Step by Step Solution

1. Step 1: Write the proportion equation
   78,723 : 123,138 = 123,138 : x
2. Step 2: Convert to fraction form
   78,723/123,138 = 123,138/x
3. Step 3: Cross multiply
   78,723x = 123,138 × 123,138
4. Step 4: Simplify right side
   78,723x = 15,162,967,044
5. Step 5: Solve for x
   x = 15,162,967,044/78,723
6. Step 6: Final answer
   x = 192,611.65