Finding the Third Proportional to 78,814 and 172,940

Step by Step Solution

1. Step 1: Write the proportion equation
   78,814 : 172,940 = 172,940 : x
2. Step 2: Convert to fraction form
   78,814/172,940 = 172,940/x
3. Step 3: Cross multiply
   78,814x = 172,940 × 172,940
4. Step 4: Simplify right side
   78,814x = 29,908,243,600
5. Step 5: Solve for x
   x = 29,908,243,600/78,814
6. Step 6: Final answer
   x = 379,478.82