Finding the Third Proportional to 78,405 and 171,823

Step by Step Solution

1. Step 1: Write the proportion equation
   78,405 : 171,823 = 171,823 : x
2. Step 2: Convert to fraction form
   78,405/171,823 = 171,823/x
3. Step 3: Cross multiply
   78,405x = 171,823 × 171,823
4. Step 4: Simplify right side
   78,405x = 29,523,143,329
5. Step 5: Solve for x
   x = 29,523,143,329/78,405
6. Step 6: Final answer
   x = 376,546.69