Finding the Third Proportional to 215,864 and 321,576

Step by Step Solution

1. Step 1: Write the proportion equation
   215,864 : 321,576 = 321,576 : x
2. Step 2: Convert to fraction form
   215,864/321,576 = 321,576/x
3. Step 3: Cross multiply
   215,864x = 321,576 × 321,576
4. Step 4: Simplify right side
   215,864x = 103,411,123,776
5. Step 5: Solve for x
   x = 103,411,123,776/215,864
6. Step 6: Final answer
   x = 479,056.83