Finding the Third Proportional to 78,878 and 172,012

Step by Step Solution

1. Step 1: Write the proportion equation
   78,878 : 172,012 = 172,012 : x
2. Step 2: Convert to fraction form
   78,878/172,012 = 172,012/x
3. Step 3: Cross multiply
   78,878x = 172,012 × 172,012
4. Step 4: Simplify right side
   78,878x = 29,588,128,144
5. Step 5: Solve for x
   x = 29,588,128,144/78,878
6. Step 6: Final answer
   x = 375,112.56