Finding the Third Proportional to 78,820 and 172,956

Step by Step Solution

1. Step 1: Write the proportion equation
   78,820 : 172,956 = 172,956 : x
2. Step 2: Convert to fraction form
   78,820/172,956 = 172,956/x
3. Step 3: Cross multiply
   78,820x = 172,956 × 172,956
4. Step 4: Simplify right side
   78,820x = 29,913,777,936
5. Step 5: Solve for x
   x = 29,913,777,936/78,820
6. Step 6: Final answer
   x = 379,520.15