Finding the Third Proportional to 78,282 and 172,428

Step by Step Solution

1. Step 1: Write the proportion equation
   78,282 : 172,428 = 172,428 : x
2. Step 2: Convert to fraction form
   78,282/172,428 = 172,428/x
3. Step 3: Cross multiply
   78,282x = 172,428 × 172,428
4. Step 4: Simplify right side
   78,282x = 29,731,415,184
5. Step 5: Solve for x
   x = 29,731,415,184/78,282
6. Step 6: Final answer
   x = 379,798.87