Finding the Third Proportional to 208,820 and 316,146

Step by Step Solution

1. Step 1: Write the proportion equation
   208,820 : 316,146 = 316,146 : x
2. Step 2: Convert to fraction form
   208,820/316,146 = 316,146/x
3. Step 3: Cross multiply
   208,820x = 316,146 × 316,146
4. Step 4: Simplify right side
   208,820x = 99,948,293,316
5. Step 5: Solve for x
   x = 99,948,293,316/208,820
6. Step 6: Final answer
   x = 478,633.72