Finding the Third Proportional to 277,700 and 419,978

Step by Step Solution

1. Step 1: Write the proportion equation
   277,700 : 419,978 = 419,978 : x
2. Step 2: Convert to fraction form
   277,700/419,978 = 419,978/x
3. Step 3: Cross multiply
   277,700x = 419,978 × 419,978
4. Step 4: Simplify right side
   277,700x = 176,381,520,484
5. Step 5: Solve for x
   x = 176,381,520,484/277,700
6. Step 6: Final answer
   x = 635,151.32