Finding the Third Proportional to 185,643 and 381,123

Step by Step Solution

1. Step 1: Write the proportion equation
   185,643 : 381,123 = 381,123 : x
2. Step 2: Convert to fraction form
   185,643/381,123 = 381,123/x
3. Step 3: Cross multiply
   185,643x = 381,123 × 381,123
4. Step 4: Simplify right side
   185,643x = 145,254,741,129
5. Step 5: Solve for x
   x = 145,254,741,129/185,643
6. Step 6: Final answer
   x = 782,441.25